Paperboard Boxes Research Articles

Enhancing sustainable food packaging design: A machine learning approach to predict ventilated corrugated paperboard strength

In the food packaging industry, ventilated corrugated paperboard boxes are crucial for sustainable transport of fresh products. While these boxes' ventilation holes advance air circulation, they also impact the material's compression or buckling strength. Variations in hole geometry and location affecting this strength are explored, considering the composite material, multi-layered structure. Traditional mechanical analyses, which often require simplifications, may not fully capture this complexity, leading to less accurate predictions of the paperboard's strength. To address these challenges, a machine learning (ML) approach was utilized, employing the Light Gradient Boosting Machine (LGBM) to develop a predictive model for the buckling strength of corrugated paperboard boxes with ventilation cutouts. This physics-informed ML model, trained on a compression dataset resulting from experimental tests for plates with a single cutout in three shapes and Finite Element Method (FEM) simulations for plates with various patterns of circular cutouts, provides highly accurate estimates of the plates' buckling strength. It achieved 91.7% accuracy on experimental data and 94.68% on FEM simulation data, showcasing its reliability. A new tool for predicting the buckling strength of corrugated paperboard is provided by this research, along with insights that can inform the design of more sustainable packaging solutions. Furthermore, the methodology and findings have broader applications, potentially benefiting sectors like aerospace and construction, where similar structural materials are used.

Numerical Modelling of Corrugated Paperboard Boxes

Numerical modelling of corrugated paperboard is quite challenging due to its waved geometry and material non-linearity which is affected by the material properties of the individual paper sheets. Because of the complex geometry and material behaviour of the board, there is still scope to enhance the accuracy of current modelling techniques as well as gain a better understanding of the structural performance of corrugated paperboard packaging for improved packaging design. In this study, four-point bending tests were carried out to determine the bending stiffness of un-creased samples in the machine direction (MD) and cross direction (CD). Bending tests were also carried out on creased samples with the fluting oriented in the CD with the crease at the centre. Inverse analysis was applied using the results from the bending tests to determine the material properties that accurately predict the bending stiffness of the horizontal creases, vertical creases, and panels of a box under compression loading. The finite element model of the box was divided into three sections, the horizontal creases, vertical creases, and the box panels. Each of these sections is described using different material properties. The box edges/corners are described using the optimal material properties from bending and compression tests conducted on creased samples, while the box panels are described using the optimal material properties obtained from four-point bending tests conducted on samples without creases. A homogenised finite element (FE) model of a box was simulated using the obtained material properties and validated using experimental results. The developed FE model accurately predicted the failure load of a corrugated paperboard box under compression with a variation of 0.1% when compared to the experimental results.

Transportation Vibration Effects on Apple Bruising

ABSTRACTVibrations during transportation often cause mechanical damage to fresh produce. Addressing or mitigating this damage requires efficient packaging solutions that maintain fresh produce integrity during transit, thereby preserving produce quality and market value. This study investigates the effects of various transportation profiles and packaging designs on apple bruising using simulated truck vibrations. Two apple varieties, Fuji and Jonagold, were packaged in corrugated paperboard boxes with paper pulp trays, plastic crates with paper pulp trays, corrugated paperboard boxes with volume packing and plastic crates with volume packing, all commercial apple packaging. The packaged apples were exposed to two random vibration profiles: leaf spring and air ride suspensions, both set at four different intensities ranging from 0.2 to 0.7 Grms for 1, 3 and 5 h. The findings revealed that both packaging type and vibration parameters significantly influenced apple bruising. Especially, plastic crates with paper pulp trays led to the most severe bruising, whereas corrugated paperboard boxes with volume packing afforded the most protection. Regardless of the packaging design, leaf spring suspension resulted in more apple bruising compared to air ride suspension. The findings of this study provide practical insights for packaging engineers to mitigate the apple bruising during transportation.

Evaluation of Recycled Paperboard Properties and Characteristics

Paperboard boxes represent a sought-after class of packaging products, where the use of recycled fibers offers a cost-effective and environmentally friendly alternative to virgin fibers. The presence of a significant proportion of recycled fibers in the paperboard leads to a number of limitations associated with the deterioration of its characteristics. In this study, the properties of coated and uncoated paperboards containing recycled fibers, wood pulp, and virgin cellulose fibers were investigated using a laboratory sample of paperboard produced from 100% recycled fibers without any chemical additives for comparison. Properties such as smoothness, bulk density, absorbency, and tensile strength, as well as colorimetric characteristics, were determined for the recycled paperboards; for the latter test, charts were printed using inkjet printing and UV-curable inks. Whiteness was calculated by three formulae (CIE, Berger, and Stensby), and all the paperboards had a relatively low whiteness (not exceeding 90 CIE), with a yellowish tint due to recycled fibers and mechanical pulp in the composition. The absence of optical brightening agents in the paperboards was experimentally confirmed. The color gamuts of the paperboards were in direct ratio to their whiteness, with the highest ones demonstrated by the coated paperboards. Color reproduction, according to the tone value increase curves, also depended on the whiteness. Uncoated paperboards demonstrated smaller color shifts than the coated ones, with the greatest increase in tone for yellow color. Coated recycled paperboards are suitable for packaging printing under the same conditions as virgin fiber boards, while uncoated boards are the recommended choice for digital printing with UV inks.

Buckling analysis of thin plates with circular cut-outs for sustainable ventilated food packaging design

Thin plates with circular cut-outs are widely used in engineering structures such as bridges, construction, and ventilated corrugated paperboard boxes in food packaging. This study investigates the critical buckling loads of thin elastic plates comprised of a single circular hole at different locations and with different sizes. To determine the critical loads, experimental tests and finite element method simulations are conducted. The vertical location and the diameter of the hole impact the buckling results significantly. The results indicate a significant correlation between the experimental and finite element data. The study develops second and third order polynomial formulas that predict buckling loads. In this study, corrugated paperboard plates were used as samples to gain insights into ventilated food packaging designs, aiming to enhance their buckling strength while reducing packaging material consumption for packaging sustainability purposes. The solution proposed in this study can be applied to predict the buckling of other elastic thin plate structures with a circular hole, relevant to industries such as construction and aerospace.

Experimental and Numerical Investigation of the In-Plane Compression of Corrugated Paperboard Panels

Finite element analysis (FEA) has been proven as a useful design tool to model corrugated paperboard boxes, and is capable of accurately predicting load capacity. The in-plane deformation, however, is usually significantly underpredicted. To investigate this discrepancy, a panel compression test jig, that implemented simply supported boundary conditions, was built to test individual panels. The panels were then modelled using non-linear FEA with a linear material model. The results show that the in-plane deformation was still underpredicted, but a general improvement was seen. Three discrepancies were identified. The first was that the panels showed an initial region of low stiffness that was not present in the FEA results. This was attributed to imperfections in the panels and jig. Secondly, the experimental results reported a lower stiffness than the FEA. Applying an initial imperfection in the shape of the first buckling mode shape was found to reduce the FEA stiffness. Thirdly, the panels showed a decrease in stiffness near failure, which was not seen in the FEA. A bi-linear material model was investigated and holds the potential to improve the results. Box compression tests were performed on a Regular Slotted Container (RSC) with the same dimensions as the tested panel. The box displaced 13.1 mm compared to 3.5 mm for the panel. There was an initial region of low stiffness, which accounted for 7 mm of displacement compared to 0.5 mm for the panels. Thus, box complexities such as horizontal creases should be included in finite element (FE) models to accurately predict the in-plane deformation, while a bi-linear (or any other non-linear) material model may be useful for panel compression.

EMPIRICAL MODELS FOR PREDICTION COMPRESSION STRENGTH OF PAPERBOARD CARTON

When designing packaging in the shape of a rectangular parallelepiped from various paperboard materials, it is important to determine their resistance to vertical compression force, which should be less than the critical compression force. This is especially relevant when the products packed in these boxes are stacked during transport or storage. The developed empirical models make it possible to more optimally / more accurately determine the critical vertical compressive strength of these packages. The purpose of this work is to create an empirical model of the critical compressive force of a paperboard box (carton) based on the corrected formulas of the critical compressive force of the McKee corrugated cardboard box (taking into account the height) of the box and allowing to optimize of its parameters. The accuracy of the developed empirical models is presented by comparing the results of theoretical and experimental studies. It should be noted that the determination of the critical compression force of the box is a contact problem of the non-linear theory of elasticity and plasticity for structures whose elements are made of an anisotropic material. On this basis, empirical models of three and one parameters were developed, which also estimated the values of experimental studies previously performed by other authors. One mathematical model also estimates the height of the box, which is not determined by the Mckee formula. For the experiments, we used cartons of different geometric parameters and made from different types of paperboard. During the experiment, the boxes were compressed with vertical force until the packages collapsed. The results of the compared theoretical and experimental studies show the suitability of the proposed mathematical models for calculating the critical compressive strength of packages since the obtained MAPE error is within acceptable limits. Taking into account the small discrepancy between the obtained experimental and theoretical research results, the proposed method for calculating the vertical critical compressive force of the rectangular parallelepiped package is suitable for use. The methodology for calculating the critical compressive strength of such packages presented in this document will be extended in the future for additional testing to verify the model with carton size and design variations.

Contribution of packaging materials to MOSH and POSH contamination of milk powder products during storage

ABSTRACT Mineral oil hydrocarbons (MOH) in milk powders, particularly in infant formulas, have been and continue to be a major concern to the public worldwide. These contaminants are likely derived from environmental pollution, manufacturing process and packaging materials. In this study, 23 Chinese commercial milk powder products packaged in four types of materials, i.e. metal cans, paper containers, paperboard boxes with internal bags, and aluminium foil-plastic bags, were collected and stored for 1 year. The total and surface MOH in these samples were detected and compared before and after storage to understand the MOH migration during storage, despite no mineral oil saturated hydrocarbons (MOAH) were detected. The contents of mineral oil saturated hydrocarbons (MOSH) and polyolefin oligomeric saturated hydrocarbons (POSH) in metal cans were the least among the four packages and changed little during storage, which suggested that little MOH migration occurred in metal material. Despite all the food contact materials in the other three packagings were the aluminium foil-plastic composite, the similar low migration occurred in the aluminium foil-plastic bags and internally contained composite bag(s) in paperboard boxes. However, both total and surface MOSH and POSH easily migrated from the paper-plastic-aluminium composite of paper containers during storage. These findings are helpful for the selection of packaging materials in manufacturing milk powder products or other foods.

Effects of Different Fluting Medium Geometries on Von-Mises Stress and Deformation in Single Fluted Board: A Three-Dimensional Finite Element Analysis

Paperboard box produced in large volume for packaging purpose either to pack light or heavy product. When a heavy product is packed, high strength and structural stability against compression and deformation of the paperboard box are demanded. This paper investigates the effects of different shape of fluting mediums on the von Mises stress and deformation using finite element analysis (FEA) tool. Solidworks and ANSYS software were used to design a 3-D model and perform static structural analysis, respectively. The result from the analysis and simulation revealed that common s-shape geometry experienced the lowest von Mises stress and deformation. Honeycomb geometry experienced the highest von Mises stress of 0.19576 MPa while triangle fluting medium recorded the highest deformation at 1.8695E-4mm.

Finite Element-Based Simulation for Edgewise Compression Behavior of Corrugated Paperboard for Packaging of Agricultural Products

Since most goods are transported and stored in a unit-load form in today’s global supply chain, there has been a growing concern regarding the compression strength of corrugated paperboard boxes for packaging of agricultural products. The best predictor of the compression strength of corrugated boxes is the edgewise compression test (ECT) value; therefore, its efficient measurement or prediction is crucial for the design of more efficient corrugated boxes for food and agricultural and industrial products. This study investigated the edgewise compression behavior (load vs. displacement plot, ECT, and failure mechanism) of corrugated paperboard based on different types of testing standards and flute types using finite element analysis (FEA) and experimental analysis. The results of this study showed that the magnitude of the ECT values produced by the FEA was different from the values produced by the experiment. The difference in the ECT can be possibly explained by layer thickness approximations, together with glue line width assumptions between fluting and the liners in the numerical models. However, the trends of the values were the same. If the material properties of corrugated paperboard components and modeling methods of the corrugated paperboard are further studied, the FE (finite element)-based simulation technique will be a useful alternative tool that can replace the edgewise compression test.

Fatigue failure and G rms –N curve of corrugated paperboard box

As a kind of transport packaging, the corrugated paperboard box is widely used in logistics. During transport, the stacked packaging units are subjected to random vibration induced by vehicles. Thus, the random dynamic force will be exerted to corrugated paperboard box continuously. As the shipping distance increases, there will be cumulative fatigue damage within the corrugated paperboard box, which will weaken the mechanical property (stiffness) and the protective value of the corrugated paperboard box. Therefore, the dynamic damage and fatigue failure of corrugated paperboard box are crucial for the design of corrugated paperboard box. This article aims to develop the acceleration root mean square-life curve of corrugated paperboard box. At first, the accelerated random vibration test method was developed by the theory analysis according to the damage equivalent principle of a specified point within the corrugated paperboard box. Then, the random vibration experiments were conducted on the loaded corrugated paperboard box by taking white noise as excitation power spectral density. In the experiments, the acceleration transmissibility curve was recorded periodically. Relative stiffness was taken as the indicator to detect the cumulative damage and assess the structural integrity of the corrugated paperboard box. The stiffness reduction 20%, 30%, and 40% were taken as fatigue failure criteria to develop the curves. Results show that both the Basquin type and exponential function type are in good fitting with the curve of the corrugated paperboard box. The index b of the Basquin type is between 8.16 and 11.01, and b′ of the exponential function type between 21.19 and 26.84. The study provides reference for the accelerated random vibration test of corrugated paperboard box.

PHYSICO-CHEMICAL CHARACTERIZATION OF SUGAR APPLE (Annona squamosa L.) FRUITS STORED WITH PVC FILM IN DIFFERENT CONTROLLED TEMPERATURES

<p class="BodyAA">Sugar apple (<em>Annona squamosa</em> L.) is tropical climacteric fruit with a very short shelf life, ripening completely in just a few days under favorable conditions. Among the techniques employed to increase the time of conservation are the use of modified atmosphere and cooling. The objective of this work was to study the use of PVC film and cooling to increase the shelf-life time of fresh fruits of sugar apple. Fruits were harvested at the stage of physiological ripeness, stored in paperboard boxes (33cm x 27cm x 10cm) covered or not with PVC film and placed in refrigerators with temperatures set to 18ºC, 21ºC, 24ºC and room temperature (average 27°C±2). The experiment was set in a completely randomized design and the treatments evaluated in a fatorial scheme 2x4 (with and without PVC film and 4 temperatures) with four replications and three fruits per plot. The results showed that lower temperatures did not affect physical-chemical characteristics of the fruits, but increased the time of post-harvesting conservation by three fold. The use of PVC film helps to preserve the weight and the external and internal quality of the fruits, but it reduced the amount of total solid soluble of the fruit pulp on the consumption point.</p>

Recycled paperboard with a barrier layer for food contact: set-off during stacking or reeling. Analytical method and preliminary results

ABSTRACTThe use of recycled paperboard for packaging dry foods is in the interest of sustainability of resources, but in most applications, the food must be protected against contamination, such as by a functional barrier on the internal surface of the paperboard box. After application, the paperboard is usually stacked or reeled before making boxes. During this period, the food-contact surface of the barrier layer is in contact with the outer side of the paperboard, which may result in set-off and subsequent contamination of food. A method is described for the determination of this path of migration, based on the taped format also used for the measurement of the barrier efficiency. Recycled paperboard containing the three surrogate substances n-heptadecane, 4-methyl benzophenone and dipropyl phthalate was taped to the food-contact side of the barrier layer. Pressure onto the test packs did not seem to be a relevant parameter. After periods of interest, a piece of the paperboard with the barrier layer was extracted and analysed for the surrogate substances. Another piece may be brought into contact with silicone paper to simulate the transfer to food. After 2 weeks at 60°C (simulating about 1 year at 25°C), set-off and the transfer to the silicone paper exceeded 1% for all barrier materials tested, but after 6 weeks at 40°C (around half a year at 25°C), set-off remained below 1% for all barrier layers except a multilayer with polyethylene on the food-contact surface. The preliminary conclusion is that set-off should be taken seriously, but may be kept low enough to provide sufficient protection of the packed food.

May polypropylene films be a sufficiently effective functional barrier for foods packed in recycled paperboard and stored at room temperature?

Bags or films of biaxially oriented polypropylene (BOPP) are widely used for packing dry foods in paperboard boxes. At room temperature, BOPP films may perform adequately as functional barrier against the migration of substances from recycled paperboard into foods. However, among other factors, the barrier efficiency strongly depends on temperature. With a glass transition temperature of around 0 °C, it still has some residual crystalline structure, but gradually loses it with every degree of rising temperature. For example, we show that at 22 °C the barrier is about 4.5-times longer effective than at 28 °C. From our results we conclude that BOPP films optimized with regard to barrier properties may adequately protect packed food against contaminants from recycled paperboard for fairly long time periods, provided temperatures are in the lower range of room temperatures.

Static and Dynamic Strength of Paperboard Containers Subjected to Variations in Climatic Conditions

The variability in climatic conditions during product distribution, especially across large distances, can be significant and is well known to affect the mechanical properties of many packaging materials. As the use of environmentally friendly materials, such as paperboard and bio‐cushions, increases, the challenge associated with overcoming the effects of extremes in temperature and relative humidity in the distribution chain becomes critical. To date, in the case of paperboard boxes, this is dealt with by accounting for the loss of static (compression) strength with increasing relative humidity. However, no method exists to address the dynamic loads induced by vehicle shocks and vibrations especially for configurations that involve stacked boxes and where the vibration intensity within the stack is influenced by the dynamic characteristic of the boxes themselves. In such scenarios, it is the variation in the stiffness of the box as a function of environmental conditions and dynamic load that needs to be established. This paper describes the evaluation of the fatigue resistance of paperboard boxes subjected to random excitation and compares the results with those obtained from quasi‐static compression tests under various environmental conditions. Results reveal a lack of correlation between the static and dynamic tests. This finding is attributed to changes in internal damping of the paperboard box samples which, when reduced, results in increased dynamic force. The paper concludes that static testing alone is insufficient to establish the fatigue resistance of stacked packaging subject to variations in climatic conditions. Copyright © 2017 John Wiley & Sons, Ltd.

Effect of Pallet Deckboard Stiffness on Corrugated Box Compression Strength

The packaging industry has long considered pallets to be rigid structures. However, in a unit load, the weight of the product produces compressive forces that are distributed across the pallet causing the top deckboards to deflect. Corrugated paperboard boxes are highly susceptible to changing support conditions; therefore, the deckboard deflection directly impacts the vertical compression strength of the box. Therefore, the objective of this study is to evaluate the effect of pallet deckboard stiffness on the vertical compression strength and deflection of corrugated paperboard boxes. Additional treatments included gaps between the deckboards and location of the box relative to the pallet stringers. Copyright © 2016 John Wiley & Sons, Ltd.

Box Compression Strength: A Crippling Approach

A crippling analysis method has been utilized to estimate the compression strength paperboard boxes. Crippling analysis is typically utilized in the aerospace industry to predict the compressive failure strength of thin, slender structures with complex cross‐sectional geometry. This type of analysis is investigated, because crippling is a simple, predictive method that can provide very good estimates of the compressive failure strength of thin, slender structures. This preliminary study investigates the possibility of applying crippling analysis to estimate paperboard box compression strength by comparing experimental and theoretical results for box compression tests of milk and cigarette boxes in various loading scenarios and with various materials. This preliminary study shows that the crippling method provides results which are almost as accurate as pre‐existing methods, although significant work remains to verify the validity and applicability of the crippling approach for paper‐based boxes. Copyright © 2015 John Wiley & Sons, Ltd.

Sensor Based on the Resonance Frequency for Detecting Overfilling in a Pressing Apparatus

When processing in the manufacture for production of paperboard boxes, there arises amount of waste paper as material, which is subsequently sent for recycling. The paper passes through the first crushing device, which ensures small pieces so that they can be transported by pipeline to a pressing apparatus. Paper material in the molding machine is forced into the pits of suitable size due to the additional handling and transport. So both pipe as well as the molding machine may be so congested with material during the failure that the equipment requires unexpected additional cleaning. The sensor detects the level of waste material in pressing device, thereby avoiding congestion in a timely manner and prevents subsequent failure. The sensor uses the resonant frequency of the oscillating rod. The microprocessor controls and evaluates the response of the rod oscillations. Sensor performance was exposed to qualification tests when it shows ability to operate also in extreme conditions such as dirty and dusty surrounding with high humidity and temperature level. Sensor detects the vibration attenuation at the poles of the rod that is caused by touching different materials. Thus may indicate changing concentration level of a material and not just pieces of paper but for example, also sand or other suitable materials or height of fluid surface.

Evaluating the Performance of Coconut Fiber and Wood Straw as Cushioning Materials to Reduce Injuries of Papaya and Mango during Transportation

For the purpose to explore more ecologically sound alternatives as cushioning materials to protect fruits against injury during transport, the objective of the research was to evaluate the performance of coconut fiber and wood straw during the simulated transport of papayas and mangoes. Tests were carried out to simulate the transport of fruits in corrugated paperboard boxes in three different packaging systems: (1) with no cushioning, (2) with coconut fiber and (3) with wood straw. Physical and physiological behaviors of papaya and mango throughout transport and storage period were studied, and the rate of injuries, weight loss, skin color and respiration rate were quantified. The results showed that the coconut fiber was more efficient than wood straw in the prevention of pulp injuries, but not in prevention of abrasions on papaya surface. In mangoes, no significant differences were found between the two cushioning materials.

Evaluating the Performance of Coconut Fiber and Wood Straw as Cushioning Materials to Reduce Injuries of Papaya and Mango during Transportation

For the purpose to explore more ecologically sound alternatives as cushioning materials to protect fruits against injury during transport, the objective of the research was to evaluate the performance of coconut fiber and wood straw during the simulated transport of papayas and mangoes. Tests were carried out to simulate the transport of fruits in corrugated paperboard boxes in three different packaging systems: (1) with no cushioning, (2) with coconut fiber and (3) with wood straw. Physical and physiological behaviors of papaya and mango throughout transport and storage period were studied, and the rate of injuries, weight loss, skin color and respiration rate were quantified. The results showed that the coconut fiber was more efficient than wood straw in the prevention of pulp injuries, but not in prevention of abrasions on papaya surface. In mangoes, no significant differences were found between the two cushioning materials.