4.1 In addition to determining the heating loss (primarily moisture content) of carbon black, these drying conditions are used to prepare samples prior to performing other carbon black tests.
4.2 When larger samples are prepared for other tests, use an open vessel of suitable dimensions so that the depth of the black is no more than 10 mm during conditioning.
4.3 Carbon black is hygroscopic. The amount of moisture absorbed is related to the surface area of the black and to the relative humidity, ambient temperature, and time to which the material is exposed.
1.1 These test methods cover the determination of the heating loss of carbon black at 125°C. This heating loss consists primarily of moisture, but other volatile materials may also be lost. These test methods are not applicable to treated carbon blacks that contain added volatile materials, if moisture loss is to be measured.