【国外标准】 Standard Test Methods for Softening Point of Hydrocarbon Resins and Rosin Based Resins by Automated Ring-and-Ball Apparatus

4.1 For hydrocarbon resins and rosin based resins, softening does not take place at a definite temperature. As the temperature rises, these materials gradually change from brittle solids or very viscous liquids to less viscous liquids. For this reason, determination of the softening point must be made by a fixed, arbitrary, and closely defined method if the results obtained are to be comparable.1.1 These test methods are intended for determining the softening point of hydrocarbon resins, rosin based resins and similar materials by means of an automated ring-and-ball apparatus. Portions are similar in technical content to the automated-apparatus versions of Test Methods D36, E28, and ISO 4625.1.1.1 The ring-and-ball softening point of a hydrocarbon resin and rosin based resins may also be determined with lower precision using the manual ring-and-ball softening point procedure in Test Methods E28.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.