| 摘要 |
<p>Paper is formed from typically cellulose fibres which have a tendency to become discoloured during processing. Thus, in order to provide good quality white paper, it is necessary to bleach that paper to limit biological activity and remove discolouration. Of concern with respect to this particular invention is also the requirement to add so-called optical brightness agents (OBA). These optical brightness agents essentially fluoresce in daylight in order to give the impression of pure white colour even though the underlying fibres are still yellow white after bleaching. Optical brightness agents are expensive and therefore the present invention provides a composition which reduces the proportion of OBA agent necessary to achieve desired base point increases in paper quality. The composition comprises peroxyacetic acid or peracetic acid and hydrogen peroxide in the relative proportions whereby the fibre surface is processed in order to be more receptive to the activities of OBA and therefore, provide greater paper quality improvement relative to the relative volume of OBA added.</p> |
