ASTM D4039-09(2023)

Standard Test Method for Reflection Haze of High-Gloss Surfaces

SIGNIFICANCE AND USE
5.1 Measured gloss values of specimens depend on the angle of illumination, refractive index of the material, and the geometric distribution of the reflected light.  
5.2 Haze is produced by irregularities in the reflecting surface that affect the distribution of flux reflected around the specular angle. The procedures specified in Test Method D523 are not designed to measure reflected-flux scattering characteristics of high-gloss finishes, particularly where specimens having different surface refractive indexes are being compared.  
5.3 In this test method, values for reflection haze are obtained from two measurements of specular gloss, one made with a large receptor aperture and the other made with a small receptor aperture. The geometric conditions have been chosen to permit the use of glossmeters that provide 60° specular gloss measurements (large receptor aperture) and 20° specular gloss measurements (small receptor aperture) as specified in Test Method D523.  
5.4 An additional method for the measurement of reflection haze is given in Test Method E430.
SCOPE
1.1 This test method describes a procedure for using two specular gloss measurements to obtain a haze index for high-gloss nonmetallic specimens (1-4).2 It is particularly useful for evaluating the haze in clear finishes on nonglossy substrates, and the haze in reflected images produced by the surfaces of opaque glossy pigmented finishes.  
1.2 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.  
1.3 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: 31-May-2023
• ICS: 87.040 - Paints and varnishes
• Technical Committee: E12 - Color and Appearance
• Drafting Committee: E12.03 - Geometry

Relations

• Refers: ASTM D3964-10(2020) - Standard Practice for Selection of Coating Specimens for Appearance Measurements
• 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 D523-14 - Standard Test Method for Specular Gloss
• Effective Date: 01-Jan-2014
• Refers: ASTM E284-13b - Standard Terminology of Appearance
• Effective Date: 01-Nov-2013
• Refers: ASTM E284-13a - Standard Terminology of Appearance
• Effective Date: 01-Jun-2013
• Refers: ASTM E284-13 - Standard Terminology of Appearance
• Effective Date: 01-Jan-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 E284-12 - Standard Terminology of Appearance
• Effective Date: 01-Jul-2012
• Refers: ASTM E430-11 - Standard Test Methods for Measurement of Gloss of High-Gloss Surfaces by Abridged Goniophotometry
• Effective Date: 01-Jun-2011
• Refers: ASTM D3964-10 - Standard Practice for Selection of Coating Specimens for Appearance Measurements
• Effective Date: 01-Jun-2010
• Refers: ASTM E284-09a - Standard Terminology of Appearance
• Effective Date: 01-Jun-2009
• Refers: ASTM E284-09 - Standard Terminology of Appearance
• Effective Date: 01-Jan-2009
• Refers: ASTM E284-08 - Standard Terminology of Appearance
• Effective Date: 01-Aug-2008
• Refers: ASTM D523-08 - Standard Test Method for Specular Gloss
• Effective Date: 01-Jun-2008
• Refers: ASTM D523-89(2008) - Standard Test Method for Specular Gloss
• Effective Date: 01-Feb-2008

Overview

ASTM D4039-09(2023) specifies the standard test method for measuring reflection haze on high-gloss, nonmetallic surfaces. Developed by ASTM International, this standard outlines a procedure that uses two specular gloss measurements to derive a haze index, providing critical information on the optical quality of high-gloss finishes. Reflection haze can significantly reduce the visual appeal and clarity of coatings, making its quantification important for manufacturers, quality control, and product development within the automotive, coatings, plastics, and related industries.

Key Topics

• Reflection Haze: Defined as the scattering of light by surface irregularities that lowers the contrast of reflected images, making glossy surfaces appear less distinct.
• Specular Gloss Measurements: This method utilizes two geometries-60° (large receptor aperture) and 20° (small receptor aperture)-to measure the gloss and compute the haze index as the difference between these values.
• Haze Index Calculation: Haze Index (H) is calculated as H = G₆₀ - G₂₀, where G₆₀ is the gloss value at 60° and G₂₀ is the gloss value at 20°, both measured per ASTM D523 specifications.
• Surface Refractive Index Dependency: Results obtained using this standard are most reliable when comparing specimens with similar surface refractive indices, as index variation affects haze index outcomes.
• Importance of Substrate and Finish: The technique is particularly valuable for evaluating the haze in clear coatings over matte substrates and in glossy, pigmented finishes producing reflected images.

Applications

The ASTM D4039-09(2023) standard test method is widely applied across industries that demand precise measurement of surface appearance attributes, especially where high-gloss finishes are critical. Key application areas include:

• Automotive Finishes: Quality assurance for car bodies and parts requiring high gloss and minimal haze for enhanced visual appeal.
• Paints and Coatings Manufacturing: Product development and QC in clear coats, varnishes, and pigmented coatings where surface haze detracts from perceived quality.
• Plastics and Polymers: Evaluation of high-gloss molded or coated plastic components for consumer electronics, appliances, and decorative items.
• Architectural and Decorative Surfaces: Consistency assessment of gloss and haze in decorative laminates, flooring, and surface panels.
• Research and Development: Material scientists and engineers use this method to benchmark and improve surface formulations for optimal appearance.

By providing an objective measurement of both gloss and reflection haze, this standard supports consistent communication of appearance specifications throughout the supply chain.

Related Standards

• ASTM D523 - Standard Test Method for Specular Gloss: The foundational method for measuring gloss at standard incident angles, referenced for glossmeter calibration and measurement geometry.
• ASTM E430 - Test Methods for Measurement of Gloss of High-Gloss Surfaces by Abridged Goniophotometry: Additional procedures for assessing reflection haze using advanced photometric techniques.
• ASTM D823 - Practices for Producing Films of Uniform Thickness: Essential for specimen preparation in coatings testing.
• ASTM D3964 - Practice for Selection of Coating Specimens for Appearance Measurements: Guidelines for selecting representative test samples.
• ASTM E284 - Terminology of Appearance: Standardized terms relevant to gloss and surface appearance measurements.

Practical Value

Implementing ASTM D4039-09(2023) enables manufacturers and laboratories to:

• Quantify Reflection Haze: Provide objective, repeatable haze index data for product specifications and performance claims.
• Ensure Product Quality: Detect and control surface defects that may affect customer perception.
• Support Regulatory Compliance: Align with international best practices for surface appearance measurement.
• Standardize Across Industries: Facilitate global trade and supplier communication by adhering to internationally recognized testing protocols.

For organizations specializing in high-gloss finishes, adherence to ASTM D4039 supports superior product quality, enhances brand reputation, and meets demanding customer expectations for appearance and performance.

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: D4039 − 09 (Reapproved 2023)
Standard Test Method for
Reflection Haze of High-Gloss Surfaces
This standard is issued under the fixed designation D4039; 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 3.1.1 specular gloss, n—ratio of flux reflected in specular
direction to incident flux for a specified angle of incidence and
1.1 This test method describes a procedure for using two
source and receptor angular apertures.
specular gloss measurements to obtain a haze index for
high-gloss nonmetallic specimens (1-4). It is particularly
3.1.2 haze, n—in reflection—scattering of light at the glossy
useful for evaluating the haze in clear finishes on nonglossy surface of a specimen responsible for the apparent reduction of
substrates, and the haze in reflected images produced by the
contrast of objects viewed by reflection at the surface.
surfaces of opaque glossy pigmented finishes.
3.2 Definitions of Terms Specific to This Standard:
1.2 This standard does not purport to address all of the
3.2.1 60° specular gloss G , n—specular gloss measured
safety concerns, if any, associated with its use. It is the
with the 60° geometry specified in Test Method D523.
responsibility of the user of this standard to establish appro-
3.2.2 20° specular gloss G , n—specular gloss measured
priate safety, health, and environmental practices and deter-
with the 20° geometry specified in Test Method D523.
mine the applicability of regulatory limitations prior to use.
3.2.3 haze index, H, n—a measure of reflection haze, where
1.3 This international standard was developed in accor-
H = G − G .
dance with internationally recognized principles on standard-
60 20
ization established in the Decision on Principles for the
3.3 Appearance terms used in this standard are defined in
Development of International Standards, Guides and Recom-
Terminology E284.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
4. Summary of Test Method
2. Referenced Documents 4.1 Measurements of 60° and 20° specular gloss are made
on a specimen. The haze index is computed as the difference
2.1 ASTM Standards:
between the two measurements.
D523 Test Method for Specular Gloss
D823 Practices for Producing Films of Uniform Thickness
4.2 This test method is applicable to nonmetallic specimens
of Paint, Coatings and Related Products on Test Panels
having a 60° specular gloss value greater than 70 in accordance
D3964 Practice for Selection of Coating Specimens for
with Test Method D523.
Appearance Measurements
4.3 Both 60° and 20° specular gloss depend upon the
E284 Terminology of Appearance
refractive index of the material being measured. Because 20°
E430 Test Methods for Measurement of Gloss of High-Gloss
gloss changes much more rapidly with index than 60° gloss,
Surfaces by Abridged Goniophotometry
the reflection haze value of a specimen also depends on the
index of refraction of the material. To establish a correction for
3. Terminology
the effect of refractive index would require its measurement for
3.1 Definitions:
each material, which is inconvenient. Comparisons of reflec-
tion haze evaluated by this test method are therefore limited to
specimens of essentially the same refractive index.
This test method is under the jurisdiction of ASTM Committee E12 on Color
and Appearance and is the direct responsibility of Subcommittee E12.03 on
Geometry.
5. Significance and Use
Current edition approved June 1, 2023. Published June 2023. Originally
approved in 1981. Last previous edition approved in 2015 as D4039 – 09 (2015).
5.1 Measured gloss values of specimens depend on the
DOI: 10.1520/D4039-09R23.
angle of illumination, refractive index of the material, and the
Boldface numbers in parentheses refer to the list of references at the end of this
geometric distribution of the reflected light.
test method.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
5.2 Haze is produced by irregularities in the reflecting
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
surface that affect the distribution of flux reflected around the
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. specular angle. The procedures specified in Test Method D523
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4039 − 09 (2023)
NOTE 1—Because of the difference in scale values for the two
are not designed to measure reflected-flux scattering character-
geometries, the haze-free standard or a haze-free specimen of refractive
istics of high-gloss finishes, particularly where specimens
index 1.527 will have a haze index H = 93.6 − 89.2 = 4.4.
having different surface refractive indexes are being compared.
5.3 In this test method, values for reflection haze are 9. Procedure
obtained from two measurements of specular gloss, one made
9.1 Select an area near the center of the test specim
...