Abstract
This paper deals with a quantitative estimation of light and heat effect on rubber and plastic sheets and films under an accelerated weathering test by a specially designed apparatus. The apparatus provides sample-holders at four different distances from a light souce (so-called Sunshine Carbon Arc) so as to exposed samples to light of different intensity. The test was made at three ambient temperatures, 7℃, 40℃ and 60°. Decreases of elongation at break are adopted as an index of degradation of samples, and expressed in the form of equations which contain three parameters such that the intensity of light exposed, the temperature of samples during the test and the time of exposure, based on the result obtained at an ambient temperature of 40℃. The values calculated by the equations thus obtained approximately agree with values observed not only at 40℃ but also at 70℃ and 60℃.
