In packaging, the use of gravure ink has a major influence on the product contained in the package in terms of protection and communication. Another purpose of the film of gravure ink is to prevent the heat transfer either from outside or from inside of the container or pack. This adherent film is not long lasting always. In order to measure thermo-elastic behavior of the film made of gravure ink, elastic and thermal properties of the same were measured. The measurements of elastic properties included the density, modulus of elasticity and Poisson's ratio. Thermal measurements were confined to thermal conductivity, specific heat, heat diffusivity and coefficient of linear expansion. It was found that temperature and relative humidity of the atmosphere had a great influence on the modulus of elasticity of the coating. The higher the temperature and relative humidity, the greater the modulus of elasticity of the coating film. It had been found that thermal conductivity of the sample decreased with increase in temperature. It was also found that the changes of ambient temperature and relative humidity influenced the thermal conductivity of the sample. The higher the temperature and relative humidity, the greater the thermal conductivity. It had been observed that coefficient of linear expansion increased sharply in the subzero temperature range and thereafter increased slowly and reached the peak value near about the temperature of +6°C and then decreased sharply. It was also observed that temperature and relative humidity greatly influenced the coefficient of linear expansion of the coating of gravure ink. The higher the temperature and relative humidity, the greater the expansion coefficient particularly after the subzero temperature range. If taken into account, these findings may be helpful for better protection, adhesion and causes of unwanted removal of such films from different metallic and non-metallic substrates.
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