Description

With the increasing demand for personalised design, traceability and anti-counterfeiting, and environmentally friendly production in the global food packaging industry, the limitations of traditional screen printing technology in terms of efficiency and flexibility are no longer sufficient to meet market demand. As a new generation of UV inkjet printing equipment, the automatic lunch box digital printing machine is designed for multi-colour printing of circular and square plastic lunch box covers and supports a variable data printing function, providing a one-stop digital printing solution for food packaging production enterprises.

1.Parameters of automatic lunch box digital printing machine

2.Product Features

The automatic lunch box digital printing machine integrates multiple core technologies such as high-speed inkjet, online detection, intelligent control, and surface pretreatment and can achieve high-quality digital printing on food-grade plastic materials such as PP, PET, PLA, etc.

(1) High-speed inkjet and high-precision printing

The equipment adopts an industrial-grade piezoelectric nozzle array, supporting flexible configuration of CMYK multicolour and optional white ink. The maximum printing resolution is 300dpi/600dpi, and the printing speed can reach 0 to 60 metres per minute. Based on actual production conditions, the equipment can complete the printing task of 6000 to 10000 meal box covers per hour, with a printing position deviation controlled within ± 0.1 millimetres. In high-resolution mode, the device can clearly print two-dimensional codes, one-dimensional codes, anti-counterfeiting codes, custom numbers, text, serial numbers, and other content containing small lines and text. The graphic format supports mainstream image files such as BMP, PDF, TIFF, JPG, etc., and is connected to external data such as EXCEL, TXT, CSV in real-time through a dynamic database interface to achieve personalised coding and printing of “one box, one code”.

（2） Intelligent online detection and automatic complement code

To ensure consistency and traceability of printing quality, the equipment is equipped with a high-speed visual inspection system that can automatically detect variable information such as one-dimensional codes, two-dimensional codes, anti-counterfeiting codes, and digital numbers on printed products in real time and compare them with the original database files one by one to timely detect quality defects such as duplicate codes, incorrect codes, bad codes, offset, and ink shortage. Once non-conforming printed materials are detected, the system will automatically issue an audible and visual alarm signal and coordinate with the waste removal mechanism to remove the waste. Specifically, for box covers that have not successfully printed codes, the device has the function of automatically supplementing codes to ensure that each product has complete data information. The detection records can also be stored in real-time in the database, generating complete detection reports and providing data support for production quality traceability.

（3） Plasma surface treatment and adhesion enhancement

The ink adhesion of plastic materials, especially low-polarity surfaces such as PP and PE, has always been a technical challenge in UV digital printing. The automatic lunch box digital printing machine integrates an online plasma surface treatment module. This technology adjusts the polarity of non-polar plastic surfaces by efficiently cleaning and activating them before printing, significantly improving the wettability and ink adhesion of the material surface. After plasma treatment, the printing substrate has a stable increase in surface dynein value, ink adhesion meets the ISO 5B standard, and the wear resistance and moisture resistance of the printed pattern are significantly enhanced. The image clarity and colour brightness are also significantly improved, and the ideal printing effect can be achieved without the need for additional adhesion promoters.

(4) High colour saturation and compatibility with multiple materials

The equipment adopts an environmentally friendly UV ink system, and the colour configuration supports CMYK+white options, achieving a high level of colour gamut coverage. Ink can be cured within seconds under the illumination of an LED-UV light source, forming an ink layer with good scratch resistance and migration resistance. Thanks to the synergistic effect of plasma surface treatment and UV curing technology, the equipment is compatible with various food-grade plastic packaging materials, including PP (polypropylene), PET (polyethylene terephthalate), OPS, and biodegradable tableware such as starch-based corn starch. The feeding thickness range of the equipment is 0 to 100 millimetres, and the maximum feeding width is 0 to 400 millimetres, which can easily meet the multi-specification printing needs of circular and square plastic lunch box covers.

3.Application scenarios

(1) Large-scale digital production of food packaging contract factories

For food packaging contract factories with an annual output of over ten million pieces, traditional screen printing technology requires separate plate making and ink adjustment for each design pattern, which is cumbersome and time-consuming. The automatic lunch box digital printing machine adopts a digital printing mode of “instant transfer and printing”, which does not require plate making and ink adjustment. It can be completed in a very short time from design confirmation to mass production. The high-speed production capacity of the equipment has enabled the daily production capacity of a single machine to exceed tens of thousands of pieces. Practical application data shows that enterprises that introduce new-generation digital printing equipment can reduce the cost of monochrome printing by 0.03 yuan/piece and increase the comprehensive printing qualification rate to 99.2%. At the same time, the equipment supports 24-hour continuous production, with a printing speed of 0 to 60 metres per minute, which can fully meet the comprehensive requirements of efficiency, cost, and quality for large-scale packaging production.

(2) Flexible packaging printing for central kitchens and pre-packaged food enterprises in chain catering

With the continuous increase in the chain rate of catering and the rapid growth of the pre-packaged food industry, the demand for customised food packaging from central kitchens and pre-packaged food enterprises is becoming increasingly strong. Enterprises not only need to maintain the consistency of the packaging visual image during large-scale production but also need to quickly update small batch packaging for seasonal limited products, regional marketing activities, and co-branded products. The flexible production capacity of the automatic lunch box digital printing machine precisely solves this contradiction. The equipment can quickly switch patterns without changing the plate, and multiple printing configurations can be flexibly combined, enabling packaging production enterprises to handle diverse customer needs in the same production batch. The actual operational data of a packaging enterprise shows that after adopting a digital printing solution, the sampling cycle is shortened by 80%, the minimum order quantity can be as low as 50 pieces, the comprehensive cost is reduced by 35%, and the pattern replacement time is compressed to 15 minutes. This on-demand production capability greatly reduces inventory pressure and material waste for enterprises.

(3) Anti-counterfeiting traceability packaging and food safety supervision system

In recent years, the requirements for anti-counterfeiting and product traceability of packaging in the global food industry have become more and more stringent. The automatic lunch box digital printing machine can read data in real time from external databases, and print variable information such as one-dimensional codes, two-dimensional codes, anti-counterfeiting codes and digital serial numbers on line to achieve a full traceability system of “one box, one code”. The online detection system combined with the equipment can compare printing data with the original database in real time, and has the function of automatically supplementing missing codes to ensure each product has complete traceability information. This function has been widely applied in the construction of food safety traceability systems for chain catering brands and in fields with high batch management requirements such as aviation catering and student nutrition meals. Printing QR codes and serial numbers on the surface of the dining box cover, consumers and regulatory authorities can quickly query the production batch, logistics information and testing reports of the product, further improving the safety and transparency of the food supply chain.

Conclusion

The automatic lunch box digital printing machine integrates high-speed inkjet, online detection, plasma surface treatment and variable data printing, to be a specialised digital printing solution for multi-color printing of circular and square plastic lunch box covers. The equipment can achieve high precision of 300dpi/600dpi, high-speed production capacity of 0 to 60 metres/minute, and is suitable for large-scale production requirements. It adopts plasma processing technology and UV curing system to guarantee the printing quality and adhesion, and the online detection and automatic coding function to guarantee the accuracy and completeness of the variable data printing. The equipment provides reliable technical support for the digital upgrading of the food packaging industry in multiple application scenarios, from large-scale food packaging contract factories, to flexible customisation of central kitchens in chain restaurants, to the construction of food safety anti-counterfeiting traceability systems.