• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.30 no.1
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• pp.53-62
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• 2024

Molded pulp products has become more attractive than traditional materials such as expanded polystyrene foam (EPS) owing to low-priced recycled paper, environmental benefits such as biodegradability, and low production cost. In this study, various design factors regarding compression and cushioning characteristics of the molded pulp cushion with truncated pyramid-shaped structural units were analyzed using a test specimen with multiple structural units. The adopted structural factors were the geometric shape, wall thickness, and depth of the structural unit. The relative humidity was set at two levels. We derived the cushion curve model of the target molded pulp cushion using the stress-energy methodology. The coefficient of determination was approximately 0.8, which was lower than that for EPS (0.98). The cushioning performance of the molded pulp cushion was affected more by the structural factors of the structural unit than by the material characteristics. Repeated impacts, higher static stress, and drop height decreased the cushioning performance. Its compression behavior was investigated in four stages: elastic, first buckling, sub-buckling, and densification. It had greater rigidity during initial deformation stages; then, during plastic deformation, the rigidity was greatly reduced. The compression behavior was influenced by structural factors such as the geometric shape and depth of the structural unit and environmental conditions, rather than material properties. The biggest difference in the compression and cushioning characteristics of molded pulp cushion compared to EPS is that it is greatly affected by structural factors, and in addition, strength and resilience are expected to decrease due to humidity and repetitive loads, so future research is needed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.5
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• pp.52-60
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• 2015

Static electricity is an imbalance of electric charges within or on the surface of a material. All packed items that are particularly sensitive to static discharge must be protected by antistatic treatment. Otherwise, static electricity generated by an electrical insulator may cause serious damages to some sensitive electronics. In order to remove or prevent a buildup of static electricity, packed items must be treated with the application of an antistatic agent, which helps any excess charge to be evenly distributed. Functional pulp tray used for packing of electronic goods was developed with application of an antistatic agent. As the concentration of the antistatic agent increased, charging voltage and surface resistance of molded pulps decreased. The increase of humidity in surrounding atmosphere around molded pulps led to the decrease of accumulation of static charges. In conclusion, the surface treatment of the antistatic agent not only reduced or eliminated buildup of static electricity in the surface, but also prevented generation of tiny dirts from molded tray.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.10a
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• pp.335-343
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• 2011

We examined the effect of the acidic liquid from carbonized rice hull(ALCRH) treatments to molded fiber packages(MFP) on weight, Haugh unit, pH and microbial activity of egg to extend the shelf life in egg packaging. Higher concentration and surface spray treatment of the acidic liquid extended the shelf life of egg. ALCRH treatment to MFP improved the performance of the packaging for egg in terms of decreased weight loss and retarded microorganism growth of eggs during storage.

• The monthly packaging world
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• s.219
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• pp.74-77
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• 2011

• Journal of the Korean Wood Science and Technology
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• v.21 no.2
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• pp.31-37
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• 1993

Composites of styrene polymers with woody fibers were prepared, and the effect of compatibilizers on their mechanical properties was evaluated. To improve the compatibility of wood fibers and the matrix polymers, styrene-maleic anhydride copolymer(SMA) and maleic anhydride-modified polymers were used as compatibilizers. As results, maleic anhydride-modified polystyrene and SMA were proved to improve the tensile strength of the molded composites, and also were evaluated as good compatibilizers for the wood fiber polystyrene composite. Cellulosic fiber (dissolving pulp) provided better reinforcement than lignocellulosic fiber(thermomechanical pulp). On the contrary in the case of the composite of wood fiber and acrylonitrile-butadiene styrene copolymer(ABS), SMA and maleic anhydride-modified acrylonitrile-butadiene-styrene copolymer(MABS) did not act as compatibilizers. However, MABS was evaluated as a good polymer matrix to make wood fiber reinforced composite. The tensile properties of the composites of wood fiber and MABS were superior than those of wood fiber-ABS composites.

• Journal of the Korean Wood Science and Technology
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• v.27 no.1
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• pp.79-87
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• 1999

To use the agricultural residues as the raw material of molded packaging material, the packaging trays were manufactured from rice-straw pulp. The physical properties were measured to compare non-treated trays with the addition trays, such as the addition of starch, rosin size, carboxymethyl cellulose(CMC), polyethylene glycol(PEG), alkylketene dimer(AKD), polyacryl amide(PAM). The results were as follows : 1. In the addition of starch, air permeability at addition of 5% was highest. Bursting strength and tensile strength were smaller than non-treated trays. 2. In the addition of rosin size, air permeability, bursting strength and tensile strength were smaller than non-treated trays. 3. In the addition of CMC, air permeability was higher than non-treated trays. Bursting strength and tensile strength were similar to non-treated trays. 4. In the addition of PEG, air permeability was higher than non-treated trays. Bursting strength at addition of 3% was the highest and tensile strength was smaller than non-treated trays. 5. In the addition of AKD, air permeability at addition of 1% and 5% was higher than non-treated trays. Bursting strength and tensile strength were smaller than non-treated trays. 6. In the addition of PAM, air permeability at addition of 0.01% was the highest. Tensile strength at addition of 0.01% were higher than non-treated trays. 7. The water absorption of the trays decreased with increasing adding of natural additives.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.1
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• pp.19-26
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• 2015

The carton for liquid products are divided into 'gable top carton' and 'aseptic carton'. Currently, these packages are being recycled in the toilet tissue manufacturing process. The recycling of the carton aluminium laminate is the most important problem facing the recycling procedure of the carton packages due to the reduction in quality of recycled materials. The polymer structure with synthetic resins being used mainly in beverage packaging is also one of the important factors for the procedure for its recycling. The objective of this study was to investigate the package material and structure of the carton for liquid products through marketing research and suggest the supplementation in the work processes of production, use, and recycling. The results represent to improve the recycling profit and the quality of recycled materials when a laminated aluminium of carton for liquid products is replaced to the transparent polymer film. The improvement of the sorting and recycling process may help their recycling efficiencies. In addition, the limited use of synthetic resin molded packaging and increase of wood-pulp collection rate will provide the improvement of the recycling profit and the quality of recycled materials.