ASTM D153-84(1996)e1

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
e1
Designation: D 153 – 84 (Reapproved 1996)
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Test Methods for
Specific Gravity of Pigments
This standard is issued under the fixed designation D 153; 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.
e NOTE—Keywords were added editorially in May 1996.
under the capillary tube than with types having the ground glass seal on
1. Scope
the inside of the neck.
1.1 These test methods cover three procedures for determin-
4.2 Water Bath, maintained at 25 6 0.5°C and equipped
ing the specific gravity of pigments, as follows:
with a stirring device.
Test Method A—For Routine Testing of Several Samples
4.3 Manometer, open- or closed-tube (see Part f of the
Simultaneously.
apparatus for Test Method C), made of glass tubing 6 mm in
Test Method B—For Tests Requiring Greater Accuracy than
diameter, fitted with rubber pressure tubing attached to a
Test Method A.
T-joint leading to the desiccator and the pump. For the
Test Method C—For Rapid and Accurate Testing of Single
open-tube type 860 mm of mercury shall be used. The
Samples.
difference in levels of the mercury in the manometer when the
1.2 The specific gravity value obtained by these procedures
system is in operation, subtracted from the barometer reading
may be used with the weight of a dry pigment to determine the
taken at the same time, shall be considered the absolute
volume occupied by the pigment in a coating formulation.
pressure of the system in millimetres of mercury.
1.3 This standard does not purport to address all of the
4.4 Desiccator, glass, constructed with heavy walls to
safety concerns, if any, associated with its use. It is the
withstand a vacuum of one atmosphere, and with an opening at
responsibility of the user of this standard to establish appro-
the side.
priate safety and health practices and determine the applica-
4.5 Vacuum Pumps—A laboratory water vacuum-type pump
bility of regulatory limitations prior to use. For specific hazard
(Note 2), to remove the greater portion of air in the desiccator,
statements, see Sections 5, 11, and 15.
and an oil vacuum-type pump, motor-driven, and capable of
2. Referenced Documents
reducing the absolute pressure of the system to 3 mm.
2.1 ASTM Standards:
NOTE 2—The water vacuum pump may be omitted if the rate of
D 1193 Specification for Reagent Water
evacuation with the oil pump can be controlled so as to avoid a rapid
ebullition of entrapped air and possible loss of specimen.
3. Purity of Reagents
4.6 Thermometer, having a range from 0 to 60°C, and
3.1 Purity of Water—Reference to water shall be understood
graduated in 0.1°C divisions.
to mean reagent water as defined by Type II of Specification
4.7 Weighing Bottle, wide-mouth cylindrical glass (about 30
D 1193.
mm in height and 70 mm in diameter), provided with a
ground-glass stopper.
TEST METHOD A—FOR ROUTINE TESTING OF
4.8 Immersion Liquid—Kerosine has been found to be a
SEVERAL SAMPLES SIMULTANEOUSLY
good wetting vehicle for most pigments, and shall be used
4. Apparatus and Materials generally as the immersion liquid. Refined, white kerosine of
narrow evaporation and boiling range shall be used. With some
4.1 Pycnometer—A pycnometer (Note 1) having a 50-mL
pigments that are not wetted well with kerosine, other immer-
capacity.
sion liquids such as glycerin, ethylene glycol, tetrahydronaph-
NOTE 1—The Weld type with the cap seal on the outside of the neck of
thalene, etc., may be substituted. The liquid must have a low
the bottle is preferred because there is less danger of trapping air just
evaporation rate and narrow boiling range, and the same
procedure shall be followed as with kerosine. Water is not a
preferred liquid because of the possibility of frothing.
These test methods are under the jurisdiction of ASTM Committee D-1 on Paint
and Related Coatings, Materials, and Applications, and are the direct responsibility
of Subcommittee D01.31 on Pigment Specifications. 5. Hazards
Current edition approved Oct. 26, 1984. Published January 1985. Originally
5.1 Before a desiccator is used for the first time, wrap it in
published as D 153 – 23 T. Last previous edition D 153 – 82.
a towel and test under an absolute pressure of under 3 mm.
Annual Book of ASTM Standards, Vol 11.01.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 153
Exercise care in handling the desiccator when under vacuum, Take the pycnometer out of the bath, allow to come to room
since a sudden jar may cause it to collapse. temperature, and weigh.
6. Standardization of Pycnometer
8. Calculation
6.1 Fill the pycnometer with freshly boiled water at 23 to
8.1 Calculate the specific gravity, S, of the pigment as
24°C, gradually bring to 25 6 0.5°C, and then dry and weigh
follows:
as specified in 7.6. Empty the pycnometer, and clean, dry, and
P
S 5 (2)
reweigh it. Next fill the pycnometer with kerosine at 23 to
K
W 2
24°C, bring to 25 6 0.5°C, dry, and weigh as before. Calculate
D
the specific gravity, S, of the kerosine at 25/25°C as follows:
where:
S 5 A/B (1)
P 5 weight of pigment used, g,
W 5 weight of water to fill the pycnometer, g,
where:
K 5 weight of kerosine added to the pigment, g, and
A 5 weight of kerosine, g, and
D 5 specific gravity of the kerosine.
B 5 weight of water, g.
7. Procedure 9. Precision
9.1 Duplicate determinations by this test method should not
7.1 Drying—Dry the pigment, preferably in an electric
oven, at 105 6 2°C for 2 h. differ by more than 0.02.
7.2 Weighing—Transfer to a clean, dry, weighed pycnom-
3 TEST METHOD B—FOR TESTS REQUIRING
eter, sufficient sample to form a layer approximately ⁄4 in. (20
GREATER ACCURACY THAN TEST METHOD A
mm) deep. For black, blue, and lake pigments of low specific
gravity, use about1gof sample; for inert crystalline pigments,
10. Apparatus (see Fig. 1 and Fig. 2)
about 4 g; for opaque white pigments, 7 to 10 g; and for red
10.1 Pycnometer, Water Bath, Manometer, Vacuum Pump,
lead, from 15 to 20 g. Weigh pigments of a hydroscopic nature
Thermometer, Weighing Bottle, and Immersion Liquid—See
from the weighing bottle.
Section 4; also Fig. 2 (e) and (f ).
7.3 Number of Specimens—Run all samples at least in
10.2 Bell Jar, glass, with a two-hole rubber stopper. Into one
duplicate.
hole of the stopper shall be fitted a separatory funnel with a
7.4 Addition of Kerosine—Add enough kerosine to the
pycnometer to form a clear layer approximately ⁄4 in. (6 mm) well-ground stopcock (Fig. 1 (c)), extending into the pycnom-
eter. Into the other hole of the stopper shall be fitted a glass
above the pigment. When necessary, stir the specimen with a
polished round-bottom glass rod until completely covered by tube with a well-ground three-way stopcock (Fig. 2 (d)) and
connected with the vacuum pump (Fig. 2 (e)). The bell jar shall
kerosine, adding more kerosine if necessary. Wash the rod with
kerosine, adding the washings to the pycnometer. rest on a sheet of rubber, cemented or vulcanized to a glass or
iron plate. With stopcock c closed and stopcock d open to the
7.5 Removal of Occluded Air—Place the pycnometer in the
pump, the system shall maintain an absolute pressure of at
desiccator. Close the desiccator and attach to the water pump
most 3 mm. A desiccator may be used instead of a bell jar.
until the greater part of the air is removed from the system.
10.3 Bottle, storage, (Fig. 2 (h)) for kerosine or other
Complete this procedure within a period of 5 to 10 min. Close
wetting liquid.
the system with a pinchcock and attach the desiccator to the oil
pump for the removal of the small amounts of air given off at
11. Hazards
the low pressures obtainable with the oil pump. Use the
manometer to indicate whether the oil pump is giving the
11.1 Before a bell jar (or desiccator) is used for the first
proper vacuum. When the manometer indicates that the abso- time, test under a vacuum as described in Section 5.
lute pressure is 3 mm and constant, cut off the oil pump for
11.2 Use a buret stopcock (Fig. 2 (c)) that is well ground
short periods, taking care that the vacuum does not change and lubricated with silicone lubricants or use a PTFE-coated
materially due to leakage. At first bubbles of air rise from the
stopcock.
pigments very rapidly, then this action gradually decreases and
fina
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