Evaluation of Jaw Profile on Heat Sealing Performance of Metallised Flexible Packages
✍ Scribed by Léa Mariza de Oliveira; José de Assis Fonseca Faria
- Book ID
- 102660432
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 930 KB
- Volume
- 9
- Category
- Article
- ISSN
- 0894-3214
No coin nor oath required. For personal study only.
✦ Synopsis
Different profiles o f jaws are used in the Brazilian market for heat sealing flexible materials used in food packaging by heated bar. The objective of this study wastoevaluatetheinfluenceof t h e j a w profileonthequalityof thetopand bott o m heat seals of pouches made of biaxially metallized polypropylene/biaxiaIly co-extruded polypropylene (BOPPmet/BOPPcoex) amd biaxially metallized polypropylene/low density polyethylene (BOPPmet/LDPE). These materials are traditionally used for snacks and ground coffee packages. Five j a w profiles were evaluated: one f l a t and four grooved, using lengthwise, crosswise a t profiles 120 and 90" and inclined. The heat sealing temperature and t i m e were optimized f o r t h e two packaging materials for all profiles. The sealing pressure was fixed a t 401bf/in2. Heat sealing quality was evaluated through visual examination, integrity, tensile strength and drop testing. All t h e tests were done before and after transport simulation on t h e packages. BOPPmet/BOPPcoex 1OOg snack packages and BOPPmet/LDPE 250g ground coffee packages were prepared under laboratory conditions. The transport simulation was done on these packages by placing them into paperboard boxes ( f o r snacks) or kraft paper sacks ( f o r ground coffee). The BOPPmet/BOPPcoex packages presented integrity problems for all t h e profiles tested. The best heat sealing, tensile strength, drop impact resistance and appearance were obtained with t h e crosswise 90 and 120" and inclined grooved profiles, therefore these profiles are t h e recommended ones for top and bottom heat sealing of snacks MOPP/met/ BOPPcoex packages. The f l a t profile had t h e worst performance among t h e ones t h a t were studied. Heat sealing quality was not affected by t h e transport simulation, for all profiles. The BOPPmet/LDPE packagesdid not show integrity problems. However, the transport simulation reduced the heat sealing quality f o r all profiles. The crosswise 120 and 90" grooved profiles showed similar performance and they are the recommended ones for BOPPmet/LDPE packaging o f ground coffee o r any product of similar appearance and density. The inclined, lengthwise and flat profiles are not recommended for these applications.