Research On Main Processing Techniqueof Cork Finishing Material

This paper mainly researched three? main processing technique of the cork finishing material including hot pressing,sectioning,and surface finish. Under the same hot-pressing curve, density weighing method was used to test the weight of cork slab in each sectioning layer and to analyze the impact of cork slab thickness on its density distribution so as to determine the optimum thickness parameter range of cork slab. To test the impact of different moisture content of cork finishing material on the roughness, thickness deviation, tool marks , it was treated in different relative humidity and same temperature conditions to absorb moisture. A layer of elastic equilibrium material between the priming and finish coat was added and it was stablized under certain different temperature and pressure conditions, the performance of paint film such as abrasive resistance, impact resistance, chromatism were tested. The results were showed as follows(1)The density distribution of cork slab showed high density in surface layer and low density in core layer by the method of frequency heating. the density deviation between the core layer and surface layer was related to the thickness of cork slab. The more thickness, the larger density deviation between surface layer and core layer.The density gradient of cork slab was not obvious when thickness of cork slab was from 60mm to 90mm; the density gradient was larger and with a 40mm of low steady density area when the thickness of cork slab was 120mm and 140mm.The optimum thickness parameter range of cork slab is 90mm with density of 520 kg/m3(2)The moisture content of cork slab had effect on surface quality of the cork finishing material, when the moisture content of cork slab was lower than 7.52%, the roughness, thickness deviation, tool marks, rejection ratio of cork finishing material was unsatisfactory; when moisture content of cork slab was between 10.7% and 14.1 %, the surface quality of cork finishing material and rejection ratio was improved significantly. The optimal moisture content of cork slab was 10.7% to obtain the ideal surface quality of cork finishing material.(3)Comparing to the traditional painting method, the painting process by adding the elastic equilibrium material between the priming and finish coat and hot pressing was better. The film abrasion value was between 0.0147 g/100r and 0.0310 g/100r, which was better than the standard value of 0.15g/100r. The dosing of elastic equilibrium material was the main factor influencing the film abrasion value, the level of significance was 0.1, the next effecting factor was hot pressing temperature and pressure, the level of significance was 0.25.The best painting processing was with 80g/m2 dosage of elastic equilibrium material, 125℃hot pressing temperature and 2MPa pressure.(4)The impact resistance property of film was better than the traditional method by adding the elastic equilibrium material between the priming and finish coat. When the impact height was lower than 50mm, there was no impact trace of film on the surface of cork flooring; when the impact height was 100mm, there was no impact trace of film on the surface of cork flooring, but with a slight rounded cave on it. When was 200mm, there was no impact trace of film on the surface of cork flooring, but with a more obvious rounded cave on it; When is 300mm or 400mm, there was a slight impact trace of film on the surface of cork flooring and obvious rounded cave.(5)The type of paint with different optical property was the main factor effecting on the surface chromatismΔE of cork flooring, after painting, the change of chromatismΔE was larger, especially the lightness turning to dark was most obvious, the change of lightness was between -13.36 and -9.13; the colour of cork flooring surface turning to red and yellow,Δa* value was between 1.6 and 3.6,Δb* was between 0.04 and 3.99.Adding the elastic equilibrium material between the priming and finish coat, the colour of cork flooring turning to darker, yellower and redder, but the change of chromatismΔE andΔL was small. The main factors effecting on theΔE was hot pressing temperature and pressure, the level of significance was 0.25.