A1 Journal article (refereed), original research

Three-dimensional Forming of Multi-layered Materials: Material Heat Response and Quality Aspects


Open Access publication

Publication Details
Authors: Ovaska Sami-Seppo, Geydt Pavel, Leminen Ville, Lyytikäinen Johanna, Matthews Sami, Tanninen Panu, Wallmeier Malte, Hauptmann Marek, Backfolk Kaj
Publisher: Rochester Institute of Technology
Publication year: 2018
Language: English
Related Journal or Series Information: Journal of Applied Packaging Research
Volume number: 10
Issue number: 3
Start page: 1
End page: 17
Number of pages: 17
ISSN: 1557-7244
JUFO-Level of this publication: 1
Open Access: Open Access publication

Abstract

The micro- and macrostructural changes occurring in multi-layered
substrates during three-dimensional forming were studied by atomic force
microscopy (AFM), scanning electron microscopy (SEM) and optical
analyses. Particular attention was paid to heat-induced deformations at
the interface between of polymeric coating layer and the paperboard.
With excessive heat transfer, occasional delamination of polyethylene
terephthalate (PET) coating from the paperboard was observed. The
mechanism behind delamination was studied in detail in-situ with
an AFM at temperatures relevant to the converting process. Based on the
analysis, the delamination could partially be linked to the widening of
the initially-existing nano-scale cracks at the coating-paperboard
interface due to the high temperature, rigid and less adhesive PET
crystallites close to the paperboard layer, and the emergence of
fissures and tensile stresses in the coating. SEM images also revealed
severe macro-scale delamination in the paperboard matrix after forming.
However, the results were somewhat conflicting, since optical and
machine vision analyses showed indisputably that both the visual quality
and the dimensional accuracy of formed trays were better at the higher
forming temperature.


Last updated on 2019-13-03 at 12:00