The effect of type and mixture of resin on the properties of impregnated paper

This study was carried out in order to investigate the effects of different types of resins and also their mixtures on the impregnated paper properties. In this regard, pure urea resin (100%), mixture of melamine and urea resins with various combinations (60/40 and 70/30 and 50/50), mixture of nano-fiber cellulose ratios of 1, 2 and 3 percent with urea resin and pure PVA (100%) were used to impregnate of newsprint basic paper of Mazandaran wood and paper industries. Immersion of samples in the impregnation step were done in two time of 5 and 10 seconds. Next, melamine resin was used for surface coating and then absorption of resin in the impregnation and coating process measured. Results showed that in the impregnation step with pure urea (100%), in the respect of absorption rate and surface properties of melamine paper, the best time of impregnation was obtained 10 seconds. In the combined treatment, adding up to 30% melamine to urea resin, as impregnation step resin, offers better properties in terms of stain resistance, cigarette resistance, resistance to cracking and resistance to hot water steam for impregnatedmade paper. By adding nanocellulose up to 1% in impregnation resin, better properties is obtained for melamine paper. Also, PVA as impregnation resin, can be offer similar quality to pure urea in the resulting melamine papers.