Study On The Resistence Property To The Sunlight Of Plastic Edge-bangings

The serious discoloration of plastic edge-bandings will directly affect product quality in their service period, this paper mainly make the quantification testing the resistence property to the sunlight of PVC edge-bangdings which were exposed to natural weather conditions and artificial UV light speeded in the use of CIE standard colorimetric characterization by instrumental method and the ocular estimate. Through large amounts of data and time tracking in-depth study, the paper obtained the following results.(1) Different parameters of X-rite SP60 integrating sphere type spectrophotometer have great influence on numerical determination of the surface material color of PVC edge-bangdings, the optimal conditions of determination is the CIE L*a*b* system and the difference formula, light source D65 (including specular reflection) and 10°field of view.(2) The resistence property to the sunlight of the rich-coloured is better than the light-coloured under sunlight in the window glass. The change of them is significantly in the initial 90 days. After 210 days, the color of the light edge-bangdings intensified and there is no significant change of the dark ones. In addition, the surpace of edge-bandings have different discoloration appearance, some become yellow and some fades white.(3) After 20 days of artificial UV light speeded, the white edge-bandings have marked change in various parameters, and other color materials do not change significantly. It is different from the characteristics changed under natural conditions. This indicates that the artificial UV light speeded has some limitations to simulate the exposure to natural weather accelerated aging. In order to ensure reproducibility of accelerated experiments, it should give full consideration to the intensity of ultraviolet ray radiation and the color changes which was caused by the wavelengths of light material.(4) The temperature have little effect on the resistence property to the sunlight PVC edge-bandings of PVC edge-bandings at the lower temperature (20℃~40℃); the temperature have a significant effect at a higher temperature (60℃~80℃).(5) Because visual method is subjective and sensitivity of the human visual to different colors are inconsistent, the best determination of the surface material color of PVC edge-bangdings is instrumental method, which can make evaluation more objectively and then for quantitative analysis. Meanwhile, the human visual determination is worth using for its consistence with the actual situationcan, so people can be combined instrumental method with the ocular estimate.(6) Considering the actual usage, the range of rich-coloured edge-bandings is less than 1.5NBS, and the light is less than 3.5 NBS. It is adept to the human visual sense for the extent of its relatively modest changes in surface color. So it can be used to an index of PVC edge-bandings'production which is to evaluate material quality of the resistence property to the sunlight.