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Abstract: In this work, recycled cellulose pulp was dried in a convective dryer and at natural environment conditions. Physical properties of the paper (moisture content, grammage, thickness, apparent and absolute densities, porosity, stretch, tension and burst resistances, dimensional stability and water absorption) were determined and the influence of the drying air temperature and velocity on the final quality of the dried paper, concerning these properties, was analyzed and compared to the paper dried at natural environment conditions. Optical and scanning electronic microscopy was employed to analyze structural changes on the paper surface after drying. The increase of both variables (temperature and air velocity) enhances the drying rates, but is harmful to the quality of the paper, leading to a final product with less uniformity and over-dried surface. [Copyright &y& Elsevier]

The properties of recycled paper are strongly affected by shrinking during drying, which depends on the drying conditions. An experimental study of the shrinkage phenomenon during drying of paper is presented. Drying experiments were conducted in a drying oven with controlled temperature. The temperature influence on shrinkage extent, porosity, and apparent density of the paper was evaluated. Structural changes on the paper surface after drying were analyzed by scanning electronic microscopy. Thickness contraction, surface, and volumetric shrinkage were correlated as a function of the moisture content. Lower apparent density values and more porous paper samples were obtained for higher temperatures. [ABSTRACT FROM AUTHOR]

Certain aspects of the handle of fabric laminates are related to properties of the component fabrics. Particular attention is paid to a theoretical prediction of the bending stiffness of a laminate from the bending and tensile properties of its components. This theoretical stiffness is a minimum value; if, in practice, the observed stiffness is much greater than this, it may generally be assumed that excess of adhesive or of melted foam is the cause. The paper also reports work on other features of the bending behaviour, such as the degree of recovery from bending, and on the shearing behaviour. The work is concluded by a brief study of some faulty laminates. [ABSTRACT FROM AUTHOR]