ASTM F1945-05(2011)

5.1 Lightfastness of printed ink jet media for specified periods of time is pertinent to the end use of these materials. Since the ability of ink jet prints to withstand color changes is a function of the spectral power distribution of the light source to which it is exposed, it is important that lightfastness be assessed under the conditions appropriate to the end use application. While ink jet prints may be handled and displayed under a variety of conditions, this practice is intended to produce the color changes that may occur in ink jet prints upon exposure to irradiation from office lighting where overhead fluorescent light is used for illumination by simulating these conditions.

5.2 The accelerated procedures covered in this practice are intended to provide a means for the rapid evaluation of the relative lightfastness of a series of prints or of a print of interest in comparison to the performance of controls with known lightfastness exposed simultaneously under laboratory conditions. Test results are useful for specification acceptance between producer and user, for quality control, and for research and product development.

5.5 Color changes may not be a linear function of duration of exposure. The preferred method of determining lightfastness is to expose the prints for a number of intervals and to assess the exposure duration required to obtain a specific color change.

1.1 This practice covers an accelerated procedure intended to determine the lightfastness of ink jet prints in office environments where overhead fluorescent light is used for illumination.

1.2 This practice describes two methods based on Method II and Method III from D4674, in which specimens are exposed to cool white VHO fluorescent lamps (Method II) and cool white fluorescent lamps (Method III) under controlled environmental conditions.

1.3 Two criteria are used to determine relative lightfastness: color change and optical density.

1.4  This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 1.5 There is no known ISO equivalent standard.