ASTM D5125-10(2014)

Standard Test Method for Viscosity of Paints and Related Materials by ISO Flow Cups

SIGNIFICANCE AND USE
5.1 This test method is useful for the determination of package and application viscosities of paints and other coatings. It is limited to Newtonian or near-Newtonian liquids.  
5.2 This test method may be used similarly to ISO 2431 in conjunction with flashpoint to determine the hazard grouping of viscous liquids in international regulations.
SCOPE
1.1 This test method covers the determination of the flow time (viscosity) of Newtonian and near-Newtonian paints, and related coatings and products using ISO capillary flow cups.  
Note 1: If the liquid is non-Newtonian, that is shear-thinning or thixotropic, Test Methods D2196 should be used.  
1.2 The cup-orifice combination (ISO cup with orifice diameter of 3 mm, 4 mm, 5 mm, or 6 mm)2 is selected to provide an efflux time with the range of 20 to 100 s and viscosities up to 700 cSt (700 mm2/s). The most commonly used cup is the one with the 4-mm orifice.  
1.3 This test method is limited to testing materials for which the breakpoint of the flow from the orifice of the flow cup can be determined with certainty. This point is difficult to determine and reproduce for materials with flow times in excess of 100 s due to slowing-down effects.  
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.  
1.5 This standard does not purport to address 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.
Note 2: The International Civil Aviation Organization (ICAO) and the International Maritime Organization (IMO) include in their regulations a similar test (ISO 2431) to determine the viscosity of hazardous viscous liquids. The viscosity is then used to place these liquids in a hazard packaging group depending on their viscosity/flashpoint relationship. The U. S. Department of Transportation permits the use of these regulations for transhipment of hazardous material within the U.S. when bound for foreign destinations.

General Information

• Status: Historical
• Publication Date: 30-Nov-2014
• ICS: 87.040 - Paints and varnishes
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.24 - Physical Properties of Liquid Paints & Paint Materials

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: D5125 − 10 (Reapproved 2014)
Standard Test Method for
Viscosity of Paints and Related Materials by ISO Flow Cups
This standard is issued under the fixed designation D5125; 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 2. Referenced Documents
2.1 ASTM Standards:
1.1 This test method covers the determination of the flow
D2196 Test Methods for Rheological Properties of Non-
time (viscosity) of Newtonian and near-Newtonian paints, and
Newtonian Materials by Rotational (Brookfield type)
related coatings and products using ISO capillary flow cups.
Viscometer
NOTE 1—If the liquid is non-Newtonian, that is shear-thinning or D3924 Specification for Environment for Conditioning and
thixotropic, Test Methods D2196 should be used.
Testing Paint, Varnish, Lacquer, and Related Materials
D3925 Practice for Sampling Liquid Paints and Related
1.2 The cup-orifice combination (ISO cup with orifice
2 Pigmented Coatings
diameter of 3 mm, 4 mm, 5 mm, or 6 mm) is selected to
E1 Specification for ASTM Liquid-in-Glass Thermometers
provide an efflux time with the range of 20 to 100 s and
2 2.2 ISO Documents:
viscosities up to 700 cSt (700 mm /s). The most commonly
ISO2431 PaintsandVarnishes:DeterminationofFlowTime
used cup is the one with the 4-mm orifice.
by Use of a Flow Cup
1.3 Thistestmethodislimitedtotestingmaterialsforwhich
3. Terminology
the breakpoint of the flow from the orifice of the flow cup can
3.1 Definitions:
be determined with certainty. This point is difficult to deter-
3.1.1 dynamic viscosity, n—the ratio of the applied shear
mine and reproduce for materials with flow times in excess of
stress to shear rate.
100 s due to slowing-down effects.
3.1.1.1 Discussion—TheSIunitfordynamicviscosityisthe
1.4 The values stated in SI units are to be regarded as
pascal second (Pas). The traditional unit is the centipoise (cP);
standard. The values given in parentheses are for information
1 cP = 1 mPas.
only.
3.1.2 flow time, n—the elapsed time from the moment when
the material under test starts to flow from the orifice of the
1.5 This standard does not purport to address the safety
filled cup to the moment when the flow stream of material first
concerns, if any, associated with its use. It is the responsibility
breaks close to the orifice.
of the user of this standard to establish appropriate safety and
health practices and determine the applicability of regulatory 3.1.3 kinematic viscosity, n—the ratio of the dynamic vis-
limitations prior to use. cosity to the density of the liquid.
3.1.3.1 Discussion—The SI unit for kinematic viscosity is
NOTE 2—The International CivilAviation Organization (ICAO) and the 2
the square metre per second (m /s). The traditional unit is the
International Maritime Organization (IMO) include in their regulations a
centistokes (cSt); 1 cSt = 1 mm /s.
similar test (ISO 2431) to determine the viscosity of hazardous viscous
liquids. The viscosity is then used to place these liquids in a hazard 3.1.4 near-Newtonian liquid, n—a liquid in which the varia-
packaging group depending on their viscosity/flashpoint relationship. The
tion of viscosity with shear rate is small and the effect on
U.S.DepartmentofTransportationpermitstheuseoftheseregulationsfor
viscosity of mechanical disturbances such as stirring is negli-
transhipment of hazardous material within the U.S. when bound for
gible.
foreign destinations.
3.1.5 Newtonian liquid, n—a liquid in which the viscosity is
independent of the shear stress or shear rate. Compare non-
Newtonian liquid.
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 D01.24 on Physical Properties of Liquid Paints and Paint Materials. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Dec. 1, 2014. Published December 2014. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1991. Last previous edition approved in 2010 as D5125 – 10. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/D5125-10R14. the ASTM website.
An ISO-type cup with an orifice diameter of 8 mm is available, but it is not Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
listed in ISO 2431 and precision and accuracy are not known. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5125 − 10 (2014)
3.1.6 non-Newtonian liquid, n—a liquid in which the ratio 6.4 Spirit Level, preferably of the circular type.
of shear stress to shear rate is not constant.
6.5 Flat Glass Plate or Straight-Edge Scraper.
4. Summary of Test Method
6.6 Stopwatch, or other suitable timing-device with scale
divisions of 0.5 s or finer and accurate to within 0.2 % when
4.1 The ISO flow cup is filled level full with the material
tested over a 60-min period.
under test that has been conditioned at the specified measuring
temperature (see 10.2.2) and the time for the material to flow
6.7 Temperature-Controlled Room or Enclosure, capable of
through one of the standard orifices is determined.
maintaining the cup and sample at a recommended, constant
temperature.
5. Significance and Use
5.1 This test method is useful for the determination of
7. Reagents and Materials
package and application viscosities of paints and other coat-
7.1 Certified kinematic viscosity standards.
ings. It is limited to Newtonian or near-Newtonian liquids.
5.2 This test method may be used similarly to ISO 2431 in 8. Sampling
conjunction with flashpoint to determine the hazard grouping
8.1 Sample material in accordance with Practice D3925.
of viscous liquids in international regulations.
8.2 Before testing, it is advisable to strain the sample
6. Apparatus
through an appropriate sieve into a clean dry container. This is
mandatory for referee purposes. Mix the material thoroughly
6.1 ISO Capillary Flow Cups—ISO cups look like Ford
while at the same time avoiding, as far as possible, loss of
cups, but instead of the non-capillary hole in the bottom of the
solvent by evaporation.
Ford cup, the ISO cup has a 20-mm capillary and is more like
a true capillary viscometer.
NOTE 4—150 mL of strained material is sufficient for one test.
6.1.1 Dimensions—The dimensions of the ISO flow cup and
the tolerances allowed in manufacture shall be as given in Fig.
9. Calibration
1. The most critical tolerance is the internal diameter of the jet
9.1 Dimensionally similar cups will give, with Newtonian
of the cup, because the flow time is inversely proportional to
liquids, such as a standard oil, similar flow times, provided that
the fourth power of this dimension. The jet of the cup shall be
the temperature of testing is precisely the same. The use of
made of stainless steel or sintered carbide unless otherwise
such liquids to calibrate cups provides a useful means of
specified, and the body of the cup shall be made of a material
initially checking that dimensionally similar cups are within
that is corrosion resistant and is not affected by the products to
the accepted tolerances of performance and also for checking
be tested.
from time to time whether any wear or damage has taken place
6.1.2 Construction—The dimensions not specified, such as
sufficient to bring a cup outside the accepted tolerances.
wall thickness, shall be such that no distortion of the cup can
9.2 For calibration of any particular cup, use a standard oil
occur in use. The external shape shown in Fig. 1 is
of known kinematic viscosity and draw a graph of kinematic
recommended, but may be modified for convenience of use, or
viscosity versus temperature from the data given by the
manufacture, provided that the protruding jet of the cup is
supplier for the oil.
protected from accidental damage as far as possible by an
external protective sleeve. Such a protective sleeve shall not be
9.3 Using the relevant procedure described in Section 1010,
immediately adjacent to the jet, so as to prevent a capillary
determine the flow of time of the oil at a known temperature
action when the material under test flows out.
within the range 20 to 30°C (68 to 80°F), measured to the
6.1.3 Finish—The interior surfaces of the cups, including
nearest 0.1°C.
the orifice, shall be smooth and free of turning marks, crevices,
9.3.1 Recordthisflowtime,whichshouldbeintherange30
ledgesandburrsthatmaycauserandomflow,ortrapsampleor
to 100 s and preferably near the midpoint of this range, to an
cleaning material. The standard of finish required is equivalent
accuracy of 0.2 s.
toamaximumroughnessofnotmorethan0.5µm(seeNote3).
9.4 From the prepared graph, read the kinematic viscosity at
NOTE3—Roughnessdefinedasthearithmeticalmeandeviation R from the test temperature.
a
the mean line of the profile.
9.4.1 Using the appropriate calibration graph of Fig. 2, Fig.
6.2 Thermometer,accurateto0.2°C(0.4°F)andgraduatedat 3, Fig. 4 or Fig. 5, read the flow time corresponding to this
kinematic viscosity.
0.1°C (0.2°F) intervals. Saybolt viscosity thermometer con-
forming to requirements
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5125 − 10 D5125 − 10 (Reapproved 2014)
Standard Test Method for
Viscosity of Paints and Related Materials by ISO Flow Cups
This standard is issued under the fixed designation D5125; 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
1.1 This test method covers the determination of the flow time (viscosity) of Newtonian and near-Newtonian paints, and related
coatings and products using ISO capillary flow cups.
NOTE 1—If the liquid is non-Newtonian, that is shear-thinning or thixotropic, Test Methods D2196 should be used.
1.2 The cup-orifice combination (ISO cup with orifice diameter of 3 mm, 4 mm, 5 mm, or 6 mm) is selected to provide an efflux
time with the range of 20 to 100 s and viscosities up to 700 cSt (700 mm /s). The most commonly used cup is the one with the
4-mm orifice.
1.3 This test method is limited to testing materials for which the breakpoint of the flow from the orifice of the flow cup can be
determined with certainty. This point is difficult to determine and reproduce for materials with flow times in excess of 100 s due
to slowing-down effects.
1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.
1.5 This standard does not purport to address 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.
NOTE 2—The International Civil Aviation Organization (ICAO) and the International Maritime Organization (IMO) include in their regulations a
similar test (ISO 2431) to determine the viscosity of hazardous viscous liquids. The viscosity is then used to place these liquids in a hazard packaging
group depending on their viscosity/flashpoint relationship. The U. S. Department of Transportation permits the use of these regulations for transhipment
of hazardous material within the U.S. when bound for foreign destinations.
2. Referenced Documents
2.1 ASTM Standards:
D2196 Test Methods for Rheological Properties of Non-Newtonian Materials by Rotational (Brookfield type) Viscometer
D3924 Specification for Environment for Conditioning and Testing Paint, Varnish, Lacquer, and Related Materials
D3925 Practice for Sampling Liquid Paints and Related Pigmented Coatings
E1 Specification for ASTM Liquid-in-Glass Thermometers
2.2 ISO Documents:
ISO 2431 Paints and Varnishes: Determination of Flow Time by Use of a Flow Cup
3. Terminology
3.1 Definitions:
3.1.1 dynamic viscosity, n—the ratio of the applied shear stress to shear rate.
This test method is under the jurisdiction of ASTM Committee D01 on Paint and Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.24 on Physical Properties of Liquid Paints &and Paint Materials.
Current edition approved July 1, 2010Dec. 1, 2014. Published July 2010December 2014. Originally approved in 1991. Last previous edition approved in 20052010 as
D5125 – 97 (2005).D5125 – 10. DOI: 10.1520/D5125-10.10.1520/D5125-10R14.
An ISO-type cup with an orifice diameter of 8 mm is available, but it is not listed in ISO 2431 and precision and accuracy are not known.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’sstandard’s Document Summary page on the ASTM website.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
3.1.1.1 Discussion—
The SI unit for dynamic viscosity is the pascal second (Pas). The traditional unit is the centipoise (cP); 1 cP = 1 mPas.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5125 − 10 (2014)
3.1.2 flow time, n—the elapsed time from the moment when the material under test starts to flow from the orifice of the filled
cup to the moment when the flow stream of material first breaks close to the orifice.
3.1.3 kinematic viscosity, n—the ratio of the dynamic viscosity to the density of the liquid.
3.1.3.1 Discussion—
The SI unit for kinematic viscosity is the square metre per second (m /s). The traditional unit is the centistokes (cSt); 1 cSt = 1
mm /s.
3.1.4 near-Newtonian liquid, n—a liquid in which the variation of viscosity with shear rate is small and the effect on viscosity
of mechanical disturbances such as stirring is negligible.
3.1.5 Newtonian liquid, n—a liquid in which the viscosity is independent of the shear stress or shear rate. Compare
non-Newtonian liquid.
3.1.6 non-Newtonian liquid, n—a liquid in which the ratio of shear stress to shear rate is not constant.
4. Summary of Test Method
4.1 The ISO flow cup is filled level full with the material under test that has been conditioned at the specified measuring
temperature (see 10.2.2) and the time for the material to flow through one of the standard orifices is determined.
5. Significance and Use
5.1 This test method is useful for the determination of package and application viscosities of paints and other coatings. It is
limited to Newtonian or near-Newtonian liquids.
5.2 This test method may be used similarly to ISO 2431 in conjunction with flashpoint to determine the hazard grouping of
viscous liquids in international regulations.
6. Apparatus
6.1 ISO Capillary Flow Cups—ISO cups look like Ford cups, but instead of the non-capillary hole in the bottom of the Ford
cup, the ISO cup has a 20-mm capillary and is more like a true capillary viscometer.
6.1.1 Dimensions—The dimensions of the ISO flow cup and the tolerances allowed in manufacture shall be as given in Fig. 1.
The most critical tolerance is the internal diameter of the jet of the cup, because the flow time is inversely proportional to the fourth
power of this dimension. The jet of the cup shall be made of stainless steel or sintered carbide unless otherwise specified, and the
body of the cup shall be made of a material that is corrosion resistant and is not affected by the products to be tested.
6.1.2 Construction—The dimensions not specified, such as wall thickness, shall be such that no distortion of the cup can occur
in use. The external shape shown in Fig. 1 is recommended, but may be modified for convenience of use, or manufacture, provided
that the protruding jet of the cup is protected from accidental damage as far as possible by an external protective sleeve. Such a
protective sleeve shall not be immediately adjacent to the jet, so as to prevent a capillary action when the material under test flows
out.
6.1.3 Finish—The interior surfaces of the cups, including the orifice, shall be smooth and free of turning marks, crevices, ledges
and burrs that may cause random flow, or trap sample or cleaning material. The standard of finish required is equivalent to a
maximum roughness of not more than 0.5 μm (see Note 3).
NOTE 3—Roughness defined as the arithmetical mean deviation R from the mean line of the profile.
a
6.2 Thermometer, accurate to 0.2°C (0.4°F) and graduated at 0.1°C (0.2°F) intervals. Saybolt viscosity thermometer conforming
to requirements for thermometer 17C and 17F (10 to 27°C) (60 to 80°F) as prescribed in Specification E1 is required. In addition,
temperature measuring devices such as non-mercury liquid-in-glass thermometers, thermocouples, or platinum resistance
thermometers that provide equivalent or better accuracy and precision, that cover the temperature range for thermometer 17C and
17F, may be used.
6.3 Stand, suitable for holding the flow cup and provided with leveling screws.
6.4 Spirit Level, preferably of the circular type.
6.5 Flat Glass Plate or Straight-Edge Scraper.
6.6 Stopwatch, or other suitable timing-device with scale divisions of 0.5 s or finer and accurate to within 0.2 % when tested
over a 60-min period.
6.7 Temperature-Controlled Room or Enclosure, capable of maintaining the cup and sample at a recommended, constant
temperature.
D5125 − 10 (2014)
FIG. 1 Flow Cup ISO
D5125 − 10 (2014)
7. Reagents and Materials
7.1 Certified kinematic viscosity standards.
8. Sampling
8.1 Sample material in accordance with Practice D3925.
8.2 Before testing, it is advisable to strain the sample through an appropriate sieve into a clean dry container. This is mandatory
for referee purposes. Mix the material thoroughly while at the same time avoiding, as far as possible, loss of solvent by
evaporation.
NOTE 4—150 mL of strained material is sufficient for one test.
9. Calibration
9.1 Dimensionally similar cups will give, with Newtonian liquids, such as a standard oil, similar flow times, provided that the
temperature of testing is precisely the same. The use of such liquids to calibrate cups provides a useful means of initially checking
that dimensionally similar cups are within the accepted tolerances of performance and also for checking from time to time whether
any wear or damage has taken place sufficient to bring a cup outside the accepted tolerances
...