ASTM D5531-94(1999)

Standard Guide for Preparation, Maintenance, and Distribution of Physical Product Standards for Color and Geometric Appearance of Coatings

SCOPE
1.1 This guide covers three levels of physical product standards for color commonly used in the coatings industry, provides terminology to describe each level, and describes techniques for generating standards.
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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-May-1999
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.26 - Optical Properties

Relations

• Replaced By: ASTM D5531-94(2003) - Standard Guide for Preparation, Maintenance, and Distribution of Physical Product Standards for Color and Geometric Appearance of Coatings
• Effective Date: 10-May-2003
• Referred By: ASTM D7195-21 - Standard Guide for Setting Object Color Specifications
• Effective Date: 10-May-1999
• Referred By: ASTM D3134-15(2019) - Standard Practice for Establishing Color and Gloss Tolerances
• Effective Date: 10-May-1999
• Referred By: ASTM D3451-06(2017) - Standard Guide for Testing Coating Powders and Powder Coatings
• Effective Date: 10-May-1999
• Referred By: ASTM D3794-22 - Standard Guide for Testing Coil Coatings
• Effective Date: 10-May-1999
• Referred By: ASTM D1729-22 - Standard Practice for Visual Appraisal of Colors and Color Differences of Diffusely-Illuminated Opaque Materials
• Effective Date: 10-May-1999

Standards Content (Sample)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 5531 – 94 (Reapproved 1999)
Standard Guide for
Preparation, Maintenance, and Distribution of Physical
Product Standards for Color and Geometric Appearance of
Coatings
This standard is issued under the fixed designation D 5531; 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 E 1331 Test Method for Reflectance Factor and Color by
Spectrophotometry Using Hemispherical Geometry
1.1 This guide covers three levels of physical product
E 1345 Practice for Reducing the Effect of Variability of
standards for color commonly used in the coatings industry,
Color Measurement by Use of Multiple Measurements
provides terminology to describe each level, and describes
E 1347 Test Method for Color and Color-Difference Mea-
techniques for generating standards.
surement by Tristimulus (Filter) Colorimetry
1.2 This standard does not purport to address all of the
E 1349 Test Method for Reflectance Factor and Color by
safety concerns, if any, associated with its use. It is the
Spectrophotometry Using Bidirectional Geometry
responsibility of the user of this standard to establish appro-
2.2 Society of Automotive Engineers Standard:
priate safety and health practices and determine the applica-
SAE J1545 Recommended Practice for Instrumental Color
bility of regulatory limitations prior to use.
Difference Measurement for Exterior Finishes, Textiles,
2. Referenced Documents
and Colored Trim
2.1 ASTM Standards:
3. Terminology
D 16 Terminology for Paint, Related Coatings, Materials
3.1 The definitions in Terminology E 284 and D 16 are
and Applications
2 applicable to this test method. The terms in E284 take
D 523 Test Method for Specular Gloss
precedence over those in D 16 if there are differences.
D 823 Practices for Producing Films of Uniform Thickness
3.2 Definitions of Terms Specific to This Standard:
of Paint, Varnish, and Related Products on Test Panels
3.2.1 concept color, n—the color of the material submitted
D 1729 Practice for Visual Evaluation of Color and Color
by the customer as the target for generating the master
Differences of Opaque Diffusely Illuminated Materials
standard.
D 2244 Test Method for Calculation of Color Differences
3.2.2 master standard, n—the physical standard for color
from Instrumentally Measured Color Coordinates
that the customer approves as the target for visual, spectropho-
D 3134 Practice for Establishing Color and Gloss Toler-
tometric, and colorimetric evaluation of all products referenced
ances
to that standard.
D 4086 Practice for Visual Evaluation of Metamerism
3.2.2.1 Discussion—in SAE J1545 this is referred to as the
D 4449 Method for Visual Evaluation of Gloss Difference
2 “official” standard.
Between Surfaces of Similar Appearance
3.2.3 duplicate master standard, n—a replicate of the mas-
E 284 Terminology of Appearance
ter standard that serves as the master standard at a secondary
E 308 Practice for Computing the Colors of Objects by
location.
Using the CIE System
3.2.3.1 Discussion—in SAE J1545 this is referred to as the
E 430 Test Methods for Measurement of Gloss of High
“reference” standard.
Gloss Surfaces by Goniophotometry
3.2.4 working standard, n—the physical product standard
E 805 Practice for Identification of Instrumental Methods of
for color used for routine measurements and visual assessments
Color or Color-Difference Measurement of Materials
in the laboratory and at the production site.
E 1164 Practice for Obtaining Spectrophotometric Data for
Object-Color Evaluation
4. Summary of Guide
4.1 Product standards are the only standards by which
1 products should be accepted or rejected for color. A master
This guide is under the jurisdiction of ASTM Committee D-1 on Paint and
Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.26 on Optical Properties.
Current edition approved April 15, 1994. Published June 1994. Available from the Society of Automotive Engineers, 400 Commonwealth Dr.,
Annual Book of ASTM Standards, Vol 06.01. Warrendale, PA 15096.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
D 5531
standard is generated from the concept color submitted by the ance) different from the final product. The concept color simply
customer. Duplicate master standards, when needed, are gen- represents the customer’s best effort to illustrate the desired
erated from the master standard. Working standards are gener- color for the coating. The concept color is to be “matched” by
ated from a duplicate master standard. They are used in the the master standard. The master standard represents the target,
laboratory or on the production line to accept or reject the color both spectrally and geometrically, for the manufactured coat-
of coatings. After initial generation, product standards must be ing. It becomes the reference by which the coating is accepted
maintained to ensure that they remain valid. This guide or rejected. Once the master standard is approved by the
considers the characteristics of product standards, factors to be customer, the concept color should be filed for possible future
considered in their creation, and factors to be considered in use.
their replacement.
7.2 The master standard is the reference for judging the
color of duplicate master standards. Although in the case of a
5. Significance and Use
major dispute it is the ultimate reference for color and
5.1 High quality physical product standards for color are the
geometric appearance, it should not be used for routine
keystone of a successful color control program. Standards are evaluations in the laboratory or at the production site.
often grouped into three major categories: product standards,
7.3 Duplicate master standards should be prepared at the
intermediate production control standards, and instrument
same time. Duplicate master standards are intended to be
standards. This guide deals only with physical product stan-
identical to the master standard. Because there will be variation
dards. Some instrumentally based color control programs use
in perceived or measured characteristics of duplicate master
“numerical standards,” derived from instrumental measure-
standards, buyer and seller must agree on tolerances for
ments of a physical product standard.
“duplicate master standards.” Fairman suggests that the mea-
sured color difference be less than 0.2 CIELAB unit, and
6. Characteristics of Physical Product Standards for
Sherman suggests that the measured color difference be less
Color
than 0.5 FMC-2 unit. SAE J1545 judges standards by stating
6.1 Physical product standards for color should be made of
that the tolerance should be the greater of 0.2 unit in each
the same material as the specimens to be evaluated. This is
CIELAB color difference component, DL*, DC*, and DH*, or
more difficult in the case of coatings because they are not
one-tenth the accepted tolerance for the product (see Practice
usually sold in their final form, that is, they may be sold as a
D 3134 and E 1345). The number of duplicate master standards
liquid or a powder but will end up as a finished film. The
to be made will depend upon the life expectancy of the color or
coating must be applied to a substrate, usually metal or paper,
product, or both, the standard’s resistance to physical abuse, its
and cured before evaluation. Agreement must be reached
cleanability, its resistance to color and geometric appearance
between the buyer and the seller on the method of application
change, and the number of times each standard will be used.
and cure for the coating before the master standard is fabri-
7.4 Each duplicate master standard should be given a unique
cated.
identification with date of fabrication. A sufficient number of
6.2 The coatings supplier should produce the physical
duplicate master standards should be generated initially to last
product standards for color. They must have the same spectral
for the lifetime of the color.
character at all viewing and illuminating geometries of concern
7.5 When a coating is manufactured at more than one
as the coating.
location, each location should treat one duplicate standard as
6.3 The standard should have the same geometric appear-
the master for that location. Another duplicate standard should
ance (nonspectr
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