Naslov
The Effect of Accelerated Ageing on Graphic paperboards Degradation

Autori
Černič-Letnar, Marjeta ; Kropar-Vančina, Vesna

Izvornik
Restaurator (0034-5806) 23 (2002); 118-132

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, izvorni, znanstveni

Ključne riječi
Graphic Paperboard; Accelerated Ageing; Degradation

Sažetak
The Effect of Accelerated Ageing on Graphic Paperboards Degradation Paper and board, now and most probably also in the future the most important carriers of written and printed cultural heritage, can be of very different permanence and durability, depending on their composition (fibres, fillers, sizing agents, dyestuffs, pigments) and on the technological con-ditions of production. We studied coated and uncoated boards from various producers and of the same grammage, (ča. 250 g/m"). The samples were submitted to accelerated ageing according to ISO 5630/3. From testing several chemical, mechanical, optical and surface qualities it became obvious that their reten-tion depended mainly upon fibre composition and type of coating pigments. Low chemical and mechanical stability is proportional to the content of thermomechanical pulp (TMP), chemo-thermo-mechanical pulp (CTMP) and recycled fibres. The changes of surface properties are strongly in-fluenced by the type of coating (binders, pigments). After ageing the surface roughness increased while absorbency both increased and decreased. The changes in optical properties of the boards were quite high ; brightness decreased while yellowness increased, both due to chemical changes in the fibre composition and the surface coating and due to the degradation of optical brighteners.

Izvorni jezik
Engleski

Znanstvena područja
Grafička tehnologija

POVEZANOST RADA