可逆热致变色油墨的色度学特性研究

本文研究了活化温度为31℃的3种含隐色染料基的热致变色油墨的色度学特性。这3种油墨具有相似的颜料粒径分布和同等厚度且对氧等离子体腐蚀相对稳定的微胶囊壳。油墨颜色与温度、引起颜色滞后的样品热史两个因素有关。比较脱色和着色过程,在CIELAB色空间中所观测的滞后环面积决定了样品上色差的大小。同一样品所能达到的最大色差是由样品不同的热史和温度决定。4个特征温度描述了引起颜色滞后的2个化学反应。当冷却到低于活化温度时,脱色状态的稳定性超过10h。热致变色效应的可逆性随着最高加热温度约呈线性降低。

Colorimetric Properties of Reversible Thermochromic Printing Inks

The colorimetric properties of three,leuco dye-based thermochromic inks at 31℃activation temperature were studied. The inks had similar pigment particle size distribution and comparably thick microcapsule shells with similar stability against oxygen plasma etching.The colour of the inks was dependent on temperature as well as the thermal history of the sample, which gives rise to colour hysteresis.The area of the observed hysteresis loop in CIELAB colour space determines how different colours appear on the sample when decolourisation and colourisation processes are compared.The largest colour difference achieved for the same sample that arose because of different thermal history and temperature were determined.Four characteristic temperatures were ascribed to the two chemical reactions causing colour hysteresis.The stability of the decolourised state at coolingactivation temperature was confirmed as10 h.The reversibility of the thermochromic effect diminished approximately linearly with the highest heating temperature.