Naslov
Optical and colour stability of graphic paperboards and prints

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

Izvornik
Acta graphica (0353-4707) 15 (2003); 13-24

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

Ključne riječi
Accelerated Ageing; Durability; Graphic Paper and Paperboard Degradation

Sažetak
In the study we investigated the influence of surface treatment on permanence and stability of various graphic paperboard types - board for books, brochures, business cards, calendars, protection package - under the conditions of accelerated ageing with increased temperature and relative humidity in the absence of light according to ISO/5630/3, and as specified for materials on paper/board of permanent value by EN/ISO9706(8). Paperboards were coated with various coating colours, and subsequently lab printed in offset technique. The effect of artificial ageing on surface properties, as well as, on image optical and colour stability was monitored. The changes observed in surface characteristics such as smoothness, roughness, air permeability, and absorptivity before and after the accelerated ageing process revealed a strong influence of coating components (pigments, binders) and surface treatment type. Increasing roughness, altering of board absorption behaviour and change in optical and colour parameters - decrease in brightness, increase in yellowness, colour shift with samples containing higher amount of optical brightening agents - were the most pronounced results. Measured differences in printing colour (dE) and optical density values indicated that colour stability of offset image approached the limit values, which are set for an image of still acceptable quality. Black (K) exhibited the highest stability among CMYK colours. Image colour stability significantly depends on surface and optical board characteristics, especially on gloss and optical brightening agent, as well as, on board fibre composition and coating pigments.

Izvorni jezik
Engleski

Znanstvena područja
Grafička tehnologija

POVEZANOST RADA