To allow cost effective mass production of reinforced thermoplastics for visible parts, in-situ a surface quality with "Class-A" standard must be achieved. Furthermore, after the application of varnish, an appearance (gloss, waviness, color) similar to that of the traditional metal component is required. Porosity and fiber readout are the common surface defects. Fiber readout results from the significantly higher volume shrinkage of the thermoplastic resin (higher CLTE) in comparison to that of the reinforcement during the cooling process in production combined with the uneven distribution of resin and fibers. While glass mat reinforced thermoplastic (GMT) parts show a disorderly readout influenced (among other factors) by fiber length. processing and fiber content of the semi-finished material, the fabric reinforced thermoplastics (organic sheets) suffer from a regular print-through-a display of the textile reinforcement. Modem tools of measurement enable one to quant @ gloss, roughness, and waviness of the surfaces. Thus parameters significantly influencing the surface characteristics can be identified. This leads to the development of procedures for improving the surface quality.

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The aim of this work was to improve the dewatering characteristics of thermo-mechanical pulp (TMP) through enzymatic treatment without any significant reduction of the quality of the end product. The cellulose and hemicellulose content of TMP was altered by means of enzymatic treatments using different purified cellulases and hemicellulases as well as commercial enzyme preparations, in order to clarify the target carbohydrate components affecting the dewatering of TMP. The effects of enzymatic treatments on the properties of the pulp as well as its forming, pressing and drying were studied by lab scale measurements. An increased dewatering rate of TMP was observed in initial drainage, wet pressing and drying laboratory experiments, as a result of various enzymatic treatments. Interestingly, both cellulose and galactoglucomannan components in TMP were found to affect the dewatering properties of the pulp, and a greatest improvement in dewatering could be obtained with a combined treatment with an endoglucanase type of cellulase and mannanase.

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Water in wet paper is located between fibers, inside of capillaries and even inside of fiber walls. Part of the water is also chemically bound as gels. This means that evaporation of water is a very complex process [