ASTM D2698-05

Standard Test Method for Determination of the Pigment Content of Solvent-Reducible Paints by High-Speed Centrifuging

SIGNIFICANCE AND USE
This test method describes a rapid method for separating pigment from solvent-reducible paints.
This test method is used by paint producers and consumers for product acceptance and process control.
SCOPE
1.1 This test method covers the separation of pigment from solvent-reducible paints and the calculation of the percent pigment from the results of nonvolatile determinations on the total paint and the separated vehicle. Note 1This test method has been proven to be applicable to most solvent-reducible paints, the exception being those paints containing severely bleeding pigments or pigments such as carbon black that are very difficult or impossible to centrifuge.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Dec-2004
• ICS: 87.060.10 - Pigments and extenders
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.21 - Chemical Analysis of Paints and Paint Materials

Relations

• Replaces: ASTM D2698-90(1999) - Standard Test Method for Determination of the Pigment Content of Solvent-Reducible Paints by High-Speed Centrifuging
• Effective Date: 01-Jan-2005
• Replaced By: ASTM D2698-05(2010) - Standard Test Method for Determination of the Pigment Content of Solvent-Reducible Paints by High-Speed Centrifuging
• Effective Date: 01-Dec-2010
• Referred By: ASTM D2372-85(2022) - Standard Practice for Separation of Vehicle From Solvent-Reducible Paints
• Effective Date: 01-Jan-2005
• Referred By: ASTM F940-99(2019)e1 - Standard Practice for Quality Control Receipt Inspection Procedures for Protective Coatings (Paint), Used in Marine Construction and Shipbuilding
• Effective Date: 01-Jan-2005
• Referred By: ASTM D2205-20 - Standard Guide for Selection of Tests for Traffic Paints
• Effective Date: 01-Jan-2005
• Referred By: ASTM D3720-90(2019) - Standard Test Method for Ratio of Anatase to Rutile in Titanium Dioxide Pigments by X-Ray Diffraction
• Effective Date: 01-Jan-2005
• Referred By: ASTM D2371-19 - Standard Test Method for Pigment Content of Solvent-Reducible Paints
• Effective Date: 01-Jan-2005

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:D2698–05
Standard Test Method for
Determination of the Pigment Content of Solvent-Reducible
1
Paints by High-Speed Centrifuging
This standard is issued under the fixed designation D2698; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope 4. Apparatus
1.1 This test method covers the separation of pigment from 4.1 Laboratory Centrifuge, capable of developing 32 000 g
3
solvent-reducible paints and the calculation of the percent or higher.
pigment from the results of nonvolatile determinations on the
5. Procedure
total paint and the separated vehicle.
5.1 Shake the sample for 10 min on a mechanical shaker,
NOTE 1—This test method has been proven to be applicable to most
stirwithapaddletoloosenanycakedpigment,andshakeagain
solvent-reducible paints, the exception being those paints containing
for10min.Ifnecessary,repeatuntiltherearenolumpspresent
severelybleedingpigmentsorpigmentssuchascarbonblackthatarevery
and the sample is thoroughly mixed.
difficult or impossible to centrifuge.
5.2 Add the mixed paint to the centrifuge container until
1.2 The values stated in SI units are to be regarded as the
sufficient paint is added to permit the recovery of 25 mL
standard. The values given in parentheses are for information
minimum of clear vehicle. Revolve the bowl at 32 000 g or
only.
higher for 15 min or until a clear vehicle is obtained.
1.3 This standard does not purport to address all of the
5.3 Transfer the vehicle carefully, so as not to dislodge any
safety concerns, if any, associated with its use. It is the
of the pigment from the walls, into a jar that is immediately
responsibility of the user of this standard to establish appro-
capped to prevent any solvent losses by evaporation. Use this
priate safety and health practices and determine the applica-
vehicle for the determination of the nonvolatile content of the
bility of regulatory limitations prior to use.
separated vehicle.
2. Referenced Documents
6. Percent Paint and Vehicle Solids
2
2.1 ASTM Standards:
6.1 Determine the percent nonvolatile content of the origi-
D2369 Test Method for Volatile Content of Coatings
nal paint and the separated vehicle in accordance with Test
Method D2369.
3. Significance and Use
3.1 Thistestmethoddescribesarapidmethodforseparating
7. Calculation
pigment from solvent-reducible paints.
7.1 Calculate the weight percent pigment of paint, P,as
3.2 This test method is used by paint producers and con-
follows:
sumers for product acceptance and process control.
P 5 ~A 2 B! 3100/100 2 B (1)
1 where:
This test method is under the jurisdiction of ASTM Committee D01 on Paint
and Related Coatings, Materials, andApplications and is the direct responsibility of
Subcommittee D01.21 on Chemical Analysis of Paints and Paint Materials.
3
Current edition approved Jan. 1, 2005. Published February 2005. Originally A supercentrifuge or a centrifuge equipped with a high-speed head have been
approved in 1965. Last previous edition approved in 1999 as D2698–90(1999). found satisfactory for this purpose.Any centrifuge capable of developing 32 000 g
DOI: 10.1520/D2698-05. and having facilities for sealing the specimen to prevent solvent loss should also
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or prove to be satisfactory.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM To calculate the gravities developed by a particular centrifuge use the following
Standards volume information, refer to the standard’s Document Summary page on calculation:
2 −5
the ASTM website. g=rotating radius, cm 3r/min 31.118 310
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D2698–05
same operator, will approximate 0.1% absolute. Two such
A = nonvolatile content of paint,%, and
valuesshouldbeconsideredsuspectiftheydifferbymorethan
B = nonvolatile content of separated vehicle,%.
0.25% absolute.
9.1.2 Reproducibility—The difference between two results,
8. Recovery of Pigment for Analysis
each the mean of duplicate determinations obtained by opera-
8.1 The pigment may be completely recovered from the
torsindifferentlaboratories,willapproximate0.25%absolute.
centrifuge bowl and washed to remove residual vehicle. This
Two such values should be considered suspect if they differ by
may be done either by a Soxhlet extraction or washing the
more than 0.5% absolute.
pigment with a suitable solvent and r
...