ASTM D717-86 pdf free.Standard Test Methods for Analysis of Magnesium Silicate Pigment.
Dry the precipitate in a weighed covered platinumcrucible. Char the paper without inflaming, burn the carbon atas low a temperature as possible，and，finally, heat with thecrucible tightly covered in an electric furnace or over a blastlamp at a temperature of 1100 to 1200°C.Cool in a desiccatorand weigh as CaO. Repeat the ignition to a constant weight.
Determine the coarse particles in accordance with TestMethods D 718,except that the specimen weight should be adjusted to provide appropriate sensitivity for the residualweight determination. Any difficulty encountered in wetting-out the specimen can be overcome by prewetting with a 50+50mixture of acetone or alcohol and water. Carefully weigh out the proportions of the standardextender pigment and standard zinc oxide mutually agreedupon, and rub up to a fairly stiff paste with a glass muller on aglass plate or stone slab with raw linseed oil conforming toSpecification D 234.Note the volume of the oil required. The test sample and reference sample shall be preparedinto suitable smooth, dry,packed surfaces in accordance withaccepted practice and tested for reflectance using the greenfilter in accordance with Test Method E 97.Data are not available to determine the precision andbias of these test methods.There are no plans at present toobtain such information. The methods have been in use forseveral years and are considered acceptable.
Reagent grade chemicals shall be used in all tests.Unless otherwise indicated, it is intended that all reagents shallconform to the specifications of the Committee on AnalyticalReagents of the American Chemical Society，where suchspecifications are available. Other grades may be used, pro-vided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accuracy ofthe determination. Unless otherwise indicated, references to water shall beunderstood to mean Type II of Specification D 1193.ASTM D717 pdf download.