Fastness properties of thermochromic

Problems associated with fastness properties of thermochromic composites remain to limit a wide range of apphcation possibUities, and at the forefront of the most important issues to be dealt with is poor fastness to UV irradiation, which excludes long-term exposure to daylight and direct sunlight, thus limiting the products for indoor use only. It was also found that temperature directly influences the properties of organic thermochromic pigments, and therefore they should be shielded from undesirable sources of heat. 

Most of the tests done to determine the fastness properties caused severe deterioration of the microcapsules, except for the mbbing, in which the microcapsules resisted major damage from the Crock-meter and retained most of their thermochromic capabilities. 

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