ASTM D1475:98(R2008) pdf free download – Standard Test Method For Density of Liquid Coatings, Inks, and Related Products.
10. Report
10.1 In reporting the density, state the test temperature to the nearest 0. 1°C, the units, and the value calculated to three places
(for example, D= x.xxx lb/gal at 25°C); state the mean, the range, and the number of replicate determinations.
The results were analyzed statistically in accordance with Practice El80. The within-laboratory coefficient of variation was found to be 0.20 % relative with 25 df and the between-laboratory coefficient of variation was 0.61 % relative with 20 df. Based on these coefficients, the following criteria should be used for judging the acceptability of results at the 95 % confidence level:
11 . I . I Repeatability—Two results, each the mean of duplicate determinations, obtained by the same operator on different days should be considered suspect if they differ by more than 0.6 % relative.
11.1.2 Reproditcibilit v—Two results, each the mean of duplicate determinations, obtained by operators in different laboratories should be considered suspect if they differ by more than 1 .8 % relative.
11.2 Inks—A separate interlaboratory study of this test method was carried out for inks. In this study. one operator in each of seven laboratories made three determinations on four different paste ink samples. Paste inks were chosen because their viscosities are high and they would be expected to provide a difficult test for the method. The inks represented a density range of 8.4 to 8.9 lb/gal and exhibited viscosities ranging from a very soft news black to a relatively heavy sheet-fed offset ink. The results were analyzed statistically in accordance with Practice E69 I. The within-laboratory standard deviation was 0.030 lb/gal and the pooled laboratory standard deviation was
0.045 lb/gal. Based on these values, the following criteria should be used for judging the acceptability of results at the 95 % confidence level:
11.2.1 Repeatability—Two results obtained by the same operator should be considered suspect if they differ by more than 0.084 lb/gal (1 %).
11.2.2 Reproducibility—Two results obtained by operators in different laboratories should be considered suspect if they differ by more than 0.125 lb/gal (1.5 %).
11.3 Bias (Paint and Inks)—Sincc there is no accepted reference material, bias cannot be determined.
12. Keywords
12. 1 density: pycnometer: weight per gallon; weight per gallon cup.