Cracking mechanisms of clay-based and GCC-based coatings
2011 (English)In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 26, no 4, p. 485-492Article in journal (Refereed) Published
Abstract [en]
A new method to produce SEM cross sections was used to analyze coated and creased samples. It was found that the binder surrounded the smaller particles leaving the large pores around the larger pigment particles. Consequently, cracks would propagate next to the large particles, and at least one crack area also showed a clear pigment surface, indicating an adhesive failure between the binder and the pigment particles. GCC and clay showed different cracking directions. GCC-based coatings showed cracks that had been initiated at the surface of the coating layer and then went through the thickness direction of the coating layer. The clay-based coatings on the other hand showed cracks that could be initiated anywhere in the thickness direction in the coating layer and then continued at an angle in the thickness direction. The cracking behaviour of the clay based coatings was probably due to anisotropic mechanical properties combined with shear stresses or out-of-plane tensile stresses during creasing.
Place, publisher, year, edition, pages
2011. Vol. 26, no 4, p. 485-492
Keywords [en]
Binder, Coating, Cracking, Creasing, Electron microscopy, Folding, Latex, Pigment, Starch, Adhesive failure, Anisotropic mechanical properties, Coating layer, Cracking mechanisms, Cross section, Large particles, Large pores, Out-of-plane, Pigment particles, Thickness direction, Binders, Crack initiation, Cracks, Latexes, Mechanical properties, Pigments, Stresses, Coatings
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-41680Scopus ID: 2-s2.0-84855547414OAI: oai:DiVA.org:ri-41680DiVA, id: diva2:1377515
2019-12-122019-12-122020-12-01Bibliographically approved