ASTM D4039-93(1999)
(Test Method)Standard Test Method for Reflection Haze of High-Gloss Surfaces
Standard Test Method for Reflection Haze of High-Gloss Surfaces
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). 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 problems, 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.
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Designation: D 4039 – 93 (Reapproved 1999)
Standard Test Method for
Reflection Haze of High-Gloss Surfaces
This standard is issued under the fixed designation D 4039; 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.
1. Scope 3.2.2 20° specular gloss G , n—specular gloss measured
with the 20° geometry specified in Test Method D 523.
1.1 This test method describes a procedure for using two
3.2.3 haze index, H, n—a measure of reflection haze, where
specular gloss measurements to obtain a haze index for
2 H 5 G −G .
high-gloss nonmetallic specimens (1-4). It is particularly 60 20
3.3 Appearance terms used in this standard are defined in
useful for evaluating the haze in clear finishes on nonglossy
Terminology E 284.
substrates, and the haze in reflected images produced by the
surfaces of opaque glossy pigmented finishes.
4. Summary of Test Method
1.2 This standard does not purport to address all of the
4.1 Measurements of 60° and 20° specular gloss are made
safety concerns, if any, associated with its use. It is the
on a specimen. The haze index is computed as the difference
responsibility of the user of this standard to establish appro-
between the two measurements.
priate safety and health practices and determine the applica-
4.2 This test method is applicable to nonmetallic specimens
bility of regulatory limitations prior to use.
having a 60° specular gloss value greater than 70° in accor-
2. Referenced Documents dance with Test Method D 523.
4.3 Both 60° and 20° specular gloss depend upon the
2.1 ASTM Standards:
refractive index of the material being measured. Because 20°
D 523 Test Method for Specular Gloss
gloss changes much more rapidly with index than 60° gloss,
D 823 Practices for Producing Films of Uniform Thickness
the reflection haze value of a specimen also depends on the
of Paint, Varnish, and Related Products on Test Panels
index of refraction of the material. To establish a correction for
D 3964 Practice for Selection of Coating Specimens for
the effect of refractive index would require its measurement for
Appearance Measurements
each material, which is inconvenient. Comparisons of reflec-
E 284 Terminology of Appearance
tion haze evaluated by this test method are therefore limited to
E 430 Test Method for Measurement of Gloss of High Gloss
specimens of essentially the same refractiive index.
Surfaces by Goniophotometry
5. Significance and Use
3. Terminology
5.1 Measured gloss values of specimens depend on the
3.1 Definitions:
angle of illumination, refractive index of the material, and the
3.1.1 specular gloss, n—ratio of flux reflected in specular
geometric distribution of the reflected light.
direction to incident flux for a specified angle of incidence and
5.2 Haze is produced by irregularities in the reflecting
source and receptor angular apertures.
surface that affect the distribution of flux reflected around the
3.1.2 haze, n—in reflection—scattering of light at the glossy
specular angle. The procedures specified in Test Method D 523
surface of a specimen responsible for the apparent reduction of
are not designed to measure reflected-flux scattering character-
contrast of objects viewed by reflection at the surface.
istics of high-gloss finishes, particularly where specimens
3.2 Definitions of Terms Specific to This Standard:
having different surface refractive indexes are being compared.
3.2.1 60° specular gloss G , n—specular gloss measured
A better index of scattering can be obtained by making two
with the 60° geometry specified in Test Method D 523.
specular reflectance measurements, that is, the use of two
receptor apertures of different size.
This test method is under the jurisdiction of ASTM Committee D-1 on Paint
5.3 In this test method, values for reflection haze are
and Related Coatings, Materials, and Applications and is the direct responsibility of
obtained from two measurements of specular gloss, one made
Subcommittee D01.26 on Optical Properties.
with a large receptor aperture and the other made with a small
Current edition approved Sept. 15, 1993. Published November 1993. Originally
receptor aperture. The geometric conditions have been chosen
published as D 4039 – 81. Last previous edition D 4039 – 92.
Boldface numbers in parentheses refer to the list of references at the end of this
to permit the use of glossmeters that provide 60° specular gloss
test method.
Annual Book of ASTM Standards, Vol 06.01.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D 4039
measurements (large receptor aperture) and 20° specular gloss 9. Procedur
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