ASTM D6279-20

Standard Test Method for Rub Abrasion Mar Resistance of High Gloss Coatings

SIGNIFICANCE AND USE
5.1 Coatings, particularly the high gloss coatings used on automobiles, boats, toys, etc., are subject to a wide variety of conditions (for example, wiping, cleaning and exposure) during manufacture and service that can mar their surface. The ability of high gloss coatings to maintain their appearance is an important product attribute. This test method provides a way to estimate the ability of high gloss coatings to resist mar damage.
SCOPE
1.1 This test method covers procedures for evaluating the relative mar resistance of a high gloss coating applied to a flat, rigid surface. Wet rub and dry rub abrasion tests are described. To fully characterize a coating's mar resistance, both tests should be run.
Note 1: Dry abrasion mar resistance can also be evaluated by using Test Methods D6037. If a very highly mar resistant coating is being evaluated, Test Methods D6037 will generally provide the better performance discrimination than the dry rub test described here. However, if the equipment described in Test Methods D6037 is not available, the dry rub test described in this test method affords a reasonable alternative. The dry rub test is also useful for evaluating coatings that are not highly mar resistant.  
1.2 Mar resistance is assessed by measuring the gloss of the abraded and unabraded areas. Mar resistance is directly related to the coating’s ability to retain gloss in abraded areas.
Note 2: The mar resistance values obtained by this test method have no absolute significance. They should only be used to derive relative performance rankings for test panels that have been prepared from the series of coatings that are currently being evaluated. If mar resistance values are quoted between laboratories, it is essential that a common standard be measured and that the values be compared to that standard. Even then, the values should be used with caution.  
1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.  
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 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.

General Information

• Status: Published
• Publication Date: 30-Nov-2020
• ICS: 25.220.99 - Other treatments and coatings
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.55 - Factory Applied Coatings on Preformed Products

Relations

• Refers: ASTM D16-24 - Standard Terminology for Paint, Related Coatings, Materials, and Applications
• Effective Date: 01-Jan-2024
• Refers: ASTM D1005-95(2020) - Standard Test Method for Measurement of Dry-Film Thickness of Organic Coatings Using Micrometers
• Effective Date: 01-Jun-2020
• Refers: ASTM D823-17 - Standard Practices for Producing Films of Uniform Thickness of Paint, Varnish, and Related Products on Test Panels
• Effective Date: 01-Dec-2017
• Refers: ASTM D16-16 - Standard Terminology for Paint, Related Coatings, Materials, and Applications
• Effective Date: 01-Jul-2016
• Refers: ASTM D3924-16 - Standard Specification for Standard Environment for Conditioning and Testing Paint, Varnish, Lacquer, and Related Materials
• Effective Date: 01-Apr-2016
• Refers: ASTM D16-14 - Standard Terminology for Paint, Related Coatings, Materials, and Applications
• Effective Date: 01-Dec-2014
• Refers: ASTM D523-14 - Standard Test Method for Specular Gloss
• Effective Date: 01-Jan-2014
• Refers: ASTM D6037-13 - Standard Test Methods for Dry Abrasion Mar Resistance of High Gloss Coatings
• Effective Date: 01-Jun-2013
• Refers: ASTM D6037-13e1 - Standard Test Methods for Dry Abrasion Mar Resistance of High Gloss Coatings
• Effective Date: 01-Jun-2013
• Refers: ASTM D823-95(2012) - Standard Practices for Producing Films of Uniform Thickness of Paint, Varnish, and Related Products on Test Panels
• Effective Date: 01-Nov-2012
• Refers: ASTM D16-12 - Standard Terminology for Paint, Related Coatings, Materials, and Applications
• Effective Date: 01-Aug-2012
• Refers: ASTM D7091-12 - Standard Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non-Ferrous Metals
• Effective Date: 01-Apr-2012
• Refers: ASTM D16-11a - Standard Terminology for Paint, Related Coatings, Materials, and Applications
• Effective Date: 01-Jun-2011
• Refers: ASTM D3924-80(2011) - Standard Specification for Standard Environment for Conditioning and Testing Paint, Varnish, Lacquer, and Related Materials
• Effective Date: 01-Jun-2011
• Refers: ASTM D16-11 - Standard Terminology for Paint, Related Coatings, Materials, and Applications
• Effective Date: 01-Jan-2011

Overview

ASTM D6279-20, titled "Standard Test Method for Rub Abrasion Mar Resistance of High Gloss Coatings," establishes procedures for evaluating the relative mar resistance of high gloss coatings when applied to flat, rigid surfaces. This standardized test is especially valuable for industries where appearance retention is critical, such as automotive, marine, and consumer goods. The method includes both wet rub and dry rub abrasion tests, allowing users to comprehensively assess a coating's ability to resist visible damage caused by rubbing, cleaning, or exposure throughout its service life.

The results from this method provide a comparative ranking of coating durability, supporting quality control and product development activities. Mar resistance is determined by measuring the gloss levels before and after abrasion, indicating the coating's ability to maintain its appearance under stress.

Key Topics

• Mar Resistance Assessment: The primary focus of ASTM D6279-20 is to test and compare the mar resistance of high gloss surfaces, relying on both wet and dry rub abrasion testing methods.
• Gloss Retention Measurement: The method utilizes glossmeters to quantitatively evaluate gloss retention, providing key data for comparing coatings.
• Relative Performance: Test results are intended for use as relative rankings within a series of coatings or systems, rather than as absolute indicators of durability.
• Versatility in Testing: When equipment for alternative methods, such as ASTM D6037, is not available, the dry rub test in D6279 offers a practical alternative for many coatings.
• Test Panel Preparation: Emphasis is placed on the uniform application of coatings, standardized conditioning, and controlled abrasion conditions to ensure reliable results.
• Applicability: While suitable for a wide range of high gloss coatings, the method is especially informative when a direct comparison among several samples is needed.
• Safety and Compliance: Users are responsible for ensuring appropriate safety, health, and environmental practices as part of the testing process.

Applications

• Automotive Clearcoats and Paints: Evaluating the rub abrasion and mar resistance of high-gloss finishes for car exteriors helps manufacturers choose coatings that maintain gloss and visual appeal under regular use and maintenance.
• Marine and Boat Finishes: High gloss marine coatings are assessed for their ability to withstand abrasion and retain sheen in demanding environments.
• Consumer Product Coatings: Toys, appliances, electronic housings, and furniture benefit from coatings tested to this standard, optimizing resistance to everyday impacts and cleaning routines.
• Coating Formulation Development: R&D teams use this method to screen new high gloss coating formulations for improved mar resistance before market introduction.
• Quality Control: Production lots are routinely tested for consistency in gloss retention after abrasion, ensuring reliability and performance in final products.
• Comparative Analysis: Coating manufacturers and applicators compare different products or batches to select and validate materials best suited for end-use requirements.

Related Standards

For comprehensive gloss measurement and surface evaluation, ASTM D6279-20 references several related ASTM standards, including:

• ASTM D16: Terminology for Paint, Related Coatings, Materials, and Applications
• ASTM D523: Test Method for Specular Gloss
• ASTM D823: Practices for Producing Films of Uniform Thickness of Paint, Coatings, and Related Products on Test Panels
• ASTM D6037: Test Methods for Dry Abrasion Mar Resistance of High Gloss Coatings
• ASTM D7091: Practice for Nondestructive Measurement of Dry Film Thickness

Adhering to these and similar standards reinforces product consistency, inter-laboratory comparability, and overall coating quality control.

---

Keywords: ASTM D6279-20, rub abrasion resistance, mar resistance, high gloss coatings, coatings testing, gloss retention, abrasion test, automotive coatings, marine coatings, quality control, standard test method, surface durability, gloss measurement.

Standards Content (Sample)

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: D6279 − 20
Standard Test Method for
Rub Abrasion Mar Resistance of High Gloss Coatings
This standard is issued under the fixed designation D6279; 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
1.1 This test method covers procedures for evaluating the 2.1 ASTM Standards:
relative mar resistance of a high gloss coating applied to a flat, D16 TerminologyforPaint,RelatedCoatings,Materials,and
rigid surface. Wet rub and dry rub abrasion tests are described. Applications
To fully characterize a coating’s mar resistance, both tests D523 Test Method for Specular Gloss
should be run. D823 Practices for Producing Films of Uniform Thickness
of Paint, Coatings and Related Products on Test Panels
NOTE 1—Dry abrasion mar resistance can also be evaluated by using
D1005 Test Method for Measurement of Dry-Film Thick-
Test Methods D6037. If a very highly mar resistant coating is being
ness of Organic Coatings Using Micrometers
evaluated, Test Methods D6037 will generally provide the better perfor-
mance discrimination than the dry rub test described here. However, if the
D3924 Specification for Standard Environment for Condi-
equipment described in Test Methods D6037 is not available, the dry rub
tioning and Testing Paint, Varnish, Lacquer, and Related
test described in this test method affords a reasonable alternative. The dry
Materials
rub test is also useful for evaluating coatings that are not highly mar
D4449 Test Method for Visual Evaluation of Gloss Differ-
resistant.
ences Between Surfaces of Similar Appearance
1.2 Mar resistance is assessed by measuring the gloss of the
D6037 Test Methods for Dry Abrasion Mar Resistance of
abraded and unabraded areas. Mar resistance is directly related
High Gloss Coatings
to the coating’s ability to retain gloss in abraded areas.
D7091 Practice for Nondestructive Measurement of Dry
NOTE 2—The mar resistance values obtained by this test method have
Film Thickness of Nonmagnetic Coatings Applied to
no absolute significance. They should only be used to derive relative
Ferrous Metals and Nonmagnetic, Nonconductive Coat-
performance rankings for test panels that have been prepared from the
ings Applied to Non-Ferrous Metals
series of coatings that are currently being evaluated. If mar resistance
values are quoted between laboratories, it is essential that a common
3. Terminology
standard be measured and that the values be compared to that standard.
Even then, the values should be used with caution.
3.1 Definitions of Terms Specific to This Standard:
1.3 The values stated in SI units are to be regarded as
3.1.1 mar resistance, n—the ability of a coating to resist
standard. The values given in parentheses are for information
permanent deformation or fracture, resulting from the applica-
only.
tion of a dynamic mechanical force.
3.1.1.1 Discussion—Thistestmethodmeasuresresistanceto
1.4 This standard does not purport to address all of the
visible damage caused by mild abrasion.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
3.2 For definitions of other terms used in this standard, refer
priate safety, health, and environmental practices and deter-
to Terminology D16.
mine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accor-
4. Summary of Test Method
dance with internationally recognized principles on standard-
4.1 The coatings that are being evaluated are applied at
ization established in the Decision on Principles for the
uniform dry film thickness to planar panels of uniform surface
Development of International Standards, Guides and Recom-
texture. After drying or curing, or both, panels are marred by
mendations issued by the World Trade Organization Technical
the action of dry abrasion media or wet abrasion media, or
Barriers to Trade (TBT) Committee.
both, under a reciprocating weighted friction pad. Mar resis-
tance is assessed by measuring the coating’s gloss within the
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 D01.55 on Factory Applied Coatings on Preformed Products. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Dec. 1, 2020. Published December 2020. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1998. Last previous edition approved in 2015 as D6279 – 15. DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/D6279-20. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6279 − 20
abraded and unabraded areas of test panels. Mar resistance is 6.7 Glossmeter,with20°geometryandamaximumwidthof
directly related to the coating’s ability to retain gloss in the measurement area of 10 mm; complying with Test Method
abraded areas. D523.
NOTE 3—For coatings that are semi- to high-gloss, a glossmeter with a
5. Significance and Use
60° geometry may be better suited. Small differences in performance
5.1 Coatings, particularly the high gloss coatings used on between highly abrasion-resistant materials are more likely to be detected
with 20° gloss measurements than with 60° gloss measurements.
automobiles, boats, toys, etc., are subject to a wide variety of
conditions (for example, wiping, cleaning and exposure) dur-
7. Preparation of Specimens
ing manufacture and service that can mar their surface. The
7.1 Prepareaminimumoftwo(2)100mmby150mm(4in.
ability of high gloss coatings to maintain their appearance is an
by 6 in.) panels for each coating that is being tested.
important product attribute.This test method provides a way to
Alternatively, if the abrader can accommodate them, larger
estimatetheabilityofhighglosscoatingstoresistmardamage.
panels such as 100 mm by 300 mm (4 in. by 12 in.) may be
6. Apparatus
used. Prepare the coated panels as described in Practices D823.
6.1 Application Equipment, as described in Practices D823.
7.2 Gloss measurements are color dependent.Abraded areas
on dark colored panels tend to give lower gloss readings than
6.2 Film Thickness Measuring Apparatus, as described in
similarly abraded areas on light colored panels. For consistent
Test Method D1005 or Test Method D7091.
results, it is recommended that testing be done using black
6.3 Abrader—The mar tester provides a reciprocating rub-
coatings. Clearcoats can be applied over a black basecoat. If it
bing motion and is so designed that the 16 mm 6 1mm
is necessary to use other colors, a black panel should be
diameter friction element moves back and forth in a straight
included as a control.
line over a 100 mm 6 10 mm (4 in. 6 0.4 in.) track on the test
panel, with a downward force of 9 N 6 10 %, at a uniform
8. Conditioning
stroke rate of 60 r/min. One cycle is a complete back and forth
8.1 Condition the test specimens at 23 °C 6 2 °C (74 °F 6
motion.
4 °F) and 50 % 6 5 % relative humidity in accordance with
6.4 Friction Pad—Cover the instrument’s friction element
Specification D3924 unl
...

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: D6279 − 15 D6279 − 20
Standard Test Method for
Rub Abrasion Mar Resistance of High Gloss Coatings
This standard is issued under the fixed designation D6279; 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 procedures for evaluating the relative mar resistance of a series of high gloss coatingscoating applied
to a flat, rigid surface. Wet rub and dry rub abrasion tests are described. To fully characterize a coating’s mar resistance, both tests
should be run.
NOTE 1—Dry abrasion mar resistance can also be evaluated by using Test Methods D6037. If a series of very highly mar resistant coatingscoating is being
evaluated, Test Methods D6037 will generally provide the better performance discrimination than the dry rub test described here. However, if the
equipment described in Test Methods D6037 is not available, the dry rub test described in this test method affords a reasonable alternative. The dry rub
test is also useful for evaluating coatings that are not highly mar resistant.
1.2 Mar resistance is assessed by measuring the gloss of the abraded and unabraded areas. Mar resistance is directly related to the
coating’scoating’s ability to retain gloss in abraded areas.
NOTE 2—The mar resistance values obtained by this test method have no absolute significance. They should only be used to derive relative performance
rankings for test panels that have been prepared from the series of coatings that are currently being evaluated. If mar resistance values are quoted between
laboratories, it is essential that a common standard be measured and that the values be compared to that standard. Even then, the values should be used
with caution.
1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.
1.4 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.5 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.
2. Referenced Documents
2.1 ASTM Standards:
D16 Terminology for Paint, Related Coatings, Materials, and Applications
D523 Test Method for Specular Gloss
D823 Practices for Producing Films of Uniform Thickness of Paint, Coatings and Related Products on Test Panels
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 D01.55 on Factory Applied Coatings on Preformed Products.
Current edition approved Dec. 1, 2015Dec. 1, 2020. Published January 2016December 2020. Originally approved in 1998. Last previous edition approved in 20132015
as D6279 – 03 (2013).D6279 – 15. DOI: 10.1520/D6279-15.10.1520/D6279-20.
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’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6279 − 20
D1005 Test Method for Measurement of Dry-Film Thickness of Organic Coatings Using Micrometers
D1186 Test Methods for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to a Ferrous
Base (Withdrawn 2006)
D1400 Test Method for Nondestructive Measurement of Dry Film Thickness of Nonconductive Coatings Applied to a
Nonferrous Metal Base (Withdrawn 2006)
D3924 Specification for Standard Environment for Conditioning and Testing Paint, Varnish, Lacquer, and Related Materials
D4449 Test Method for Visual Evaluation of Gloss Differences Between Surfaces of Similar Appearance
D6037 Test Methods for Dry Abrasion Mar Resistance of High Gloss Coatings
D7091 Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals
and Nonmagnetic, Nonconductive Coatings Applied to Non-Ferrous Metals
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 mar resistance, n—the ability of a coating to resist permanent deformation or fracture, resulting from the application of a
dynamic mechanical force.
3.1.1.1 Discussion—
This test method measures resistance to visible damage caused by mild abrasion.
3.2 For definitions of other terms used in this standard, refer to Terminology D16.
4. Summary of Test Method
4.1 The coatings that are being evaluated are applied at uniform dry film thickness to planar panels of uniform surface texture.
After drying or curing, or both, panels are marred by the action of dry abrasion media or wet abrasion media, or both, under a
reciprocating weighted friction pad. Mar resistance is assessed by measuring the coating’s gloss within the abraded and unabraded
areas of test panels. Mar resistance is directly related to the coating’s ability to retain gloss in abraded areas.
5. Significance and Use
5.1 Coatings, particularly the high gloss coatings used on automobiles, boats, toys, etc., are subject ofto a wide variety of
conditions (for example, wiping, cleaning and exposure) during manufacture and service that can mar their surface. The ability of
high gloss coatings to maintain their appearance is an important product attribute. This test method provides a way to estimate the
ability of high gloss coatings to resist mar damage.
6. Apparatus
6.1 Application Equipment, as described in Practices D823.
6.2 Film Thickness Measuring Apparatus, as described in Test MethodsMethod D1005, D1186or Test Method D1400D7091.
6.3 Abrader—The mar tester provides a reciprocating rubbing motion and is so designed that the 16 mm, 61 mm diameter,
friction element with a downward force of 9 N, 610 %, mm 6 1 mm diameter friction element moves back and forth in a straight
line over a 100 mm 6 10 mm (4 inin. 6 0.4 in.) track on the test panel. It has a panel, with a downward force of 9 N 6 10 %,
at a uniform stroke rate of 60 r/min. One revolutioncycle is a complete back and forth motion.
6.4 Friction Pad—Cover the instrument’s friction element with a pad made of felt or paper. Felt pads can be attached by wrapping
the felt around the friction element and holding it in place with a suitable spring clip or clamp. Paper pads must be cut to fit to
cover the area of the friction element that contacts the coating. They can be attached to the friction element with two-sided tape
or paper pads that can be purchased with an adhesive backing. The type of pad affects the abrasion and so must be defined for the
test. test by the interested parties. It has been found that generally a thicker felt pad works best for dry abrasion and a thinner paper
pad is best for wet abrasion.
6.4.1 Felt pads can be attached by wrapping the felt around the friction element and holding it in place with a suitable spring clip
or clamp.
A list of machines suitable for this purpose is found in Research Report RR:D01-1117. Contact ASTM Customer Service at [e-mail].
D6279 − 20
6.4.2 Paper pads must be cut so they cover the area of the friction element that contacts the coating. They can be attached to the
friction element with two-sided tape.
6.5 Dry Abrasion Media—Feldspar/calcite, non-silicate cleaning powder.
6.6 Wet Abrasion Media—Prepare an aluminum oxide (grit) slurry as follows:
aluminum oxide (220 mesh) 10.0 (by weight)
polyacrylic acid 6.0
distilled water 83.3
2-aminopropanol 0.7
Total 100.0
6.6.1 The slurry ingredients can be combined by using a mixer or spatula. The slurry gets very thick, but is easy to mix.
6.6.2 The slurry prepared by this formula should have a pH of 7.9 to 8.0 and a viscosity of 190 P to 210 P (as measured on a
rotational viscometer with a spindle
...