1.1 本试验方法描述了不透明和透明塑料薄膜和固体塑料光泽的测量程序。它包含四个单独的光泽角度( 注1 ): 1.1.1 60度，建议用于中等光泽薄膜， 1.1.2 20度，建议用于高光泽薄膜， 1.1.3 45度，建议用于中等和低光泽薄膜， 1.1.4 85度，建议用于中等和低光泽薄膜，以及 1.1.5 75度，建议用于塑料壁板和拱腹。 注1: 85度、75度、60度和20度的仪器和测量方法与试验方法中的相同 D523 和 D3679 ; 45°程序的测试方法类似 C346 . 1.2 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 注2: 没有已知的ISO等效于本标准。 1.3 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 镜面光泽主要用于衡量薄膜和表面的光泽外观。只有当光泽值涉及相同的测量程序和相同的一般材料类型时，精确比较光泽值才有意义。特别是，不应将透明膜的光泽度值与不透明膜的光泽度值进行比较，反之亦然。光泽是表面的一个复杂属性，无法用任何单个数字完全测量。 4.2 镜面光泽通常随表面平滑度和平整度而变化。 它有时用于比较测量这些表面特性。

1.1 This test method describes procedures for the measurement of gloss of plastic films and solid plastics, both opaque and transparent. It contains four separate gloss angles ( Note 1 ): 1.1.1 60-deg, recommended for intermediate-gloss films, 1.1.2 20-deg, recommended for high-gloss films, 1.1.3 45-deg, recommended for intermediate and low-gloss films, 1.1.4 85-deg, recommended for intermediate and low gloss films, and 1.1.5 75-deg, recommended for plastic siding and soffit. Note 1: The 85-deg, 75-deg, 60-deg, and 20-deg apparatus and method of measurement duplicate those in Test Method D523 and D3679 ; those for the 45° procedure are similarly taken from Test Method C346 . 1.2 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. Note 2: There is no known ISO equivalent to this standard. 1.3 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. ====== Significance And Use ====== 4.1 Specular gloss is used primarily as a measure of the shiny appearance of films and surfaces. Precise comparisons of gloss values are meaningful only when they refer to the same measurement procedure and same general type of material. In particular, gloss values for transparent films should not be compared with those for opaque films, and vice versa. Gloss is a complex attribute of a surface which cannot be completely measured by any single number. 4.2 Specular gloss usually varies with surface smoothness and flatness. It is sometimes used for comparative measurements of these surface properties.