ASTM D3721-05(2019)

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.
Designation: D3721 −05 (Reapproved 2019)
Standard Specification for
Synthetic Red Iron Oxide Pigment
This standard is issued under the fixed designation D3721; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
Fe O , min, % 96.0
2 3
Moisture and other volatile matter, max, % 1.0
1.1 This specification covers synthetic red iron oxide for use
Organic coloring matter none
Coarse particles (total residue retained on a 45-µm 1.0
in paints and coatings manufactured by any of the following:
(No. 325) sieve) max, %
1.1.1 Calcination of iron salts.
Matter soluble in water, max, % 0.2
1.1.2 Precipitation from iron salts. pH value, min 5.0
1.1.3 Calcination of synthetic iron oxide.
3.2 Inasmuchasironoxidepigmentsareavailableinarange
1.1.4 Product of organic reduction.
of colors, the mass color and, if desired by the purchaser, the
character of the tint formed by mixture with a white pigment
1.2 This international standard was developed in accor-
shall be within mutually agreed upon limits of a reference
dance with internationally recognized principles on standard-
sample mutually agreed upon between the seller and the
ization established in the Decision on Principles for the
purchaser. This sample should be tested in accordance with
Development of International Standards, Guides and Recom-
Test Method D387.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
4. Sampling
2. Referenced Documents
4.1 Two samples shall be taken at random from different
packages from each lot, batch, day’s pack, or other unit of
2.1 ASTM Standards:
production in a shipment. When no markings distinguishing
D50 Test Methods for ChemicalAnalysis ofYellow, Orange,
between units of production appear samples shall be taken
Red, and Brown Pigments Containing Iron and Manga-
from different packages in the ratio of two samples for each
nese
10 000 lb (5000 kg), except that for shipments of less than
D185 Test Methods for Coarse Particles in Pigments
10 000 lb two samples shall be taken. At the option of the
D280 Test Methods for Hygroscopic Moisture (and Other
purchaser, the samples may be tested separately, or after
Matter Volatile Under the Test Conditions) in Pigments
blending in equal quantities the samples from the same
D387 Test Method for Color and Strength of Chromatic
production unit to form a composite sample.
Pigments with a Mechanical Muller
D1208 Test Methods for Common Properties of Certain
5. Test Methods
Pigmen
...