ASTM D478-02
(Specification)Standard Specification for Zinc Yellow (Zinc Chromate) Pigments
Standard Specification for Zinc Yellow (Zinc Chromate) Pigments
SCOPE
1.1 This specification covers the pigments commercially known as zinc yellow (zinc chromate).
1.2 Two types are included:
1.2.1 Type I—High-purity, low sulfate and chloride content.
1.2.2 Type IIRegular grade.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D 478 – 02
Standard Specification for
1
Zinc Yellow (Zinc Chromate) Pigments
This standard is issued under the fixed designation D 478; 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 (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
TABLE 1 Composition Requirements
1. Scope
Type I Type II
1.1 This specification covers the pigments commercially
Zinc (calculated as ZnO), % 35 to 40 35 to 40
known as zinc yellow (zinc chromate).
Chromium (calculated as CrO ), 41 41
3
1.2 Two types are included:
min, %
A
1.2.1 Type I—High-purity, low sulfate and chloride content.
Sulfates (calculated as SO ), max, % 0.20 3.0
3
A
Chlorides (calculated as Cl), max, % 0.10 0.8
1.2.2 Type II—Regular grade.
Alkaline salts (calculated as K O), max, % 13 13
2
Matter insoluble in acetic acid 0.3 0.3
2. Referenced Documents
(1+9) at 80°C, max, %
Moisture and other volatile matter, max, % 1.0 1.0
2.1 ASTM Standards:
Coarse particles (total residue retained on 1.0 1.0
D 185 Test Methods for Coarse Particles in Pigments,
No. 325 (45-µm) sieve), max, %
2
Pastes, and Paints
A
The maximum percent of sulfates or chlorides given in the table for Type II
D 387 Test Method for Color and Strength of Color Pig-
pigment apply if only one or the other is present (for this purpose amounts of less
3
ments with a Mechanical Muller than 0.05 % shall be disregarded). If both sulfates and chlorides are present, the
sum of the percentages of each divided by its respective maximum permissible
D 444 Test Methods for Chemical Analysis of Zinc Yellow
percentage (3.0 for SO and 0.8 for Cl) shall not exceed 1.0. For example, if a
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2
Pigment (Zinc Chromate Yellow)
sample contains 1.8 % SO (0.6 of the maximum for sulfates) and 0.3 % chlorides
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(0.4 of the maximum for chlorides), the sample just conforms to the maximum
requirements of the specification in this respect.
3. Significance and Use
3.1 Zinc yellow is used in rust-inhibiting protective coatings
and metal primers for ferrous and non-ferrous metals.
production in a shipment. When no markings distinguishing
4. Composition and Properties
between units of production appear, samples shall be taken
4.1 Dry Pigment—The pigment shall be a reaction precipi- from different packages in the ratio of two samples for each
10 000 lb (4545 kg), except that for shipments of less than
tate of soluble chromates and a suitable zinc compound and
shall be free of extenders, carbonates, and organic color in any 10 000 lb two samples shall be taken.
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