ASTM C584-81(2016)

Standard Test Method for Specular Gloss of Glazed Ceramic Whitewares and Related Products

SIGNIFICANCE AND USE
4.1 This test method provides a means of establishing specular gloss limits for bright, semi-mat, and mat glazed surfaces. It is realized that specular gloss measurements do not always correlate well with visual rankings of glossiness because specular gloss is only one of several related appearance attributes that produce the sensation of gloss. However, the prescribed test method is of sufficient accuracy for the intended purpose.  
Note 1: If a greater degree of distinction between bright glazed surfaces is desired, the 20° geometry instrument will provide it.4
SCOPE
1.1 This test method covers the determination of 60° specular gloss of glazed ceramic whitewares and related products.  
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: Published
• Publication Date: 30-Jun-2016
• ICS: 81.060.20 - Ceramic products
• Technical Committee: C21 - Ceramic Whitewares and Related Products
• Drafting Committee: C21.03 - Methods for Whitewares and Environmental Concerns

Relations

• Replaces: ASTM C584-81(2011) - Standard Test Method for Specular Gloss of Glazed Ceramic Whitewares and Related Products
• Effective Date: 01-Jul-2016
• Refers: ASTM D523-14 - Standard Test Method for Specular Gloss
• Effective Date: 01-Jan-2014
• 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
• Refers: ASTM D523-89(1999) - Standard Test Method for Specular Gloss
• Effective Date: 10-May-1999
• Referred By: ASTM E179-17(2022) - Standard Guide for Selection of Geometric Conditions for Measurement of Reflection and Transmission Properties of Materials
• Effective Date: 01-Jul-2016

Overview

ASTM C584-81(2016), Standard Test Method for Specular Gloss of Glazed Ceramic Whitewares and Related Products, is an internationally recognized standard developed by ASTM International. This standard specifies a precise method for determining the 60° specular gloss of glazed ceramic whitewares and similar materials. Specular gloss is an important attribute that influences the aesthetic and functional properties of ceramic products, impacting areas such as product differentiation, quality control, and visual appeal.

This method provides a reliable means to establish gloss limits for bright, semi-mat, and mat glazed surfaces, offering sufficient accuracy for its intended applications. It also references guidelines for instrument geometry, calibration, and sample preparation to ensure consistent and reproducible results.

Key Topics

• Scope and Purpose: Defines the method for measuring the 60° specular gloss of glazed ceramic whitewares and related products. Specular gloss measurements, while not always directly correlating with visual gloss perception, serve as a standardized metric for comparing materials.
• Instrumentation: Outlines requirements for glossmeters, including the use of incandescent light sources, prescribed aperture sizes, and receptor geometry. Instructions specify placing the receptor at a 60° angle to the specimen's surface normal, which is standard for industrial gloss measurements.
• Gloss Standards: Utilizes primary working standards (highly polished black glass) and secondary standards (e.g., calibrated ceramic tiles) for instrument calibration and verification.
• Test Specimen Preparation: Details size requirements (minimum 102 x 102 mm), cleaning protocols, and condition of surfaces to ensure accuracy.
• Measurement Procedure: Involves averaging two readings at right angles to minimize the effects of surface anisotropies.
• Reporting: Specifies the need to record material type, gloss value, instrument details, and working standards used during the test.

Applications

ASTM C584-81(2016) is widely used in the ceramics industry for:

• Quality Assurance: Ensures glazed ceramic whitewares (such as tiles, dinnerware, and sanitary ware) meet consistent gloss standards during manufacturing.
• Product Development: Assesses appearance attributes for new glazes, assisting manufacturers in achieving targeted visual effects (e.g., glossy, semi-gloss, or matte finishes).
• Specification Compliance: Helps manufacturers and buyers verify that products meet specific gloss requirements required in contracts or markets.
• Comparative Analysis: Allows researchers and quality control labs to compare materials, batches, or product samples using a standardized gloss measurement method.
• Troubleshooting and Process Control: Identifies variations in glazing processes or raw materials that may impact gloss, enabling timely adjustments.

Related Standards

• ASTM D523 - Standard Test Method for Specular Gloss: A broader test method for specular gloss, referenced by ASTM C584 and applicable to a wide range of materials beyond ceramics.
• ISO 2813 - Paints and Varnishes - Determination of Gloss Value at 20°, 60°, and 85°: An international standard with similar methodology, often cross-referenced in industries requiring harmonized measurement practices.
• ASTM C21 - Standard Terminology of Ceramic Whitewares and Related Products: Defines key terms and concepts relevant to the ceramics industry.
• ASTM C373 - Standard Test Method for Water Absorption, Bulk Density, Apparent Porosity, and Apparent Specific Gravity of Fired Whiteware Products: A complementary standard for physical property characterization of ceramic products.

Keywords: ASTM C584, specular gloss, glazed ceramic whitewares, gloss measurement, glossmeter, ceramic tiles, quality control, ceramic product testing, surface appearance, visual gloss, standard test method.

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: C584 − 81 (Reapproved 2016)
Standard Test Method for
Specular Gloss of Glazed Ceramic Whitewares and Related
Products
This standard is issued under the fixed designation C584; 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.
NOTE 1—If a greater degree of distinction between bright glazed
1. Scope
surfaces is desired, the 20° geometry instrument will provide it.
1.1 This test method covers the determination of 60° specu-
lar gloss of glazed ceramic whitewares and related products.
5. Apparatus
1.2 This standard does not purport to address all of the
5.1 Instrumental Components—The apparatus shall consist
safety concerns, if any, associated with its use. It is the
of an incandescent light source and lens furnishing an incident
responsibility of the user of this standard to establish appro-
beam of rays of required aperture, means for locating the
priate safety and health practices and determine the applica-
surface of the specimen, and a receptor located to receive the
bility of regulatory limitations prior to use.
required pyramid of rays reflected from the specimen. The
receptor shall be a photosensitive device having maximum
2. Referenced Documents
response near the middle of the visible region of the specimen.
2.1 ASTM Standards:
5.2 Geometric Conditions—The axis of the incident beam
D523 Test Method for Specular Gloss
shall be 60° from the perpendicular to the specimen surface.
The axis of the receptor beam shall be coincident with the
3. Terminology
mirror image of the axis of the incident beam. A flat piece of
3.1 Definitions:
polished black glass in the specimen position shall form an
3.1.1 specular gloss—the ratio of reflected to incident light,
image of the source in the center of the receptor window. The
times 1000, for specified apertures of illumination and recep-
length of the illuminated area of the specimen shall be equal to
tionwhentheaxisofreceptioncoincideswiththemirrorimage
notmorethanonethirdthedistancefromthecenterofthisarea
of the axis of illumination.
to the receptor field stop.The axis of the incident beam and the
axis of the receptor shall be within 0.1° of the nominal value
4. Significance and Use
indicated by the geometry. The dimensions and tolerances of
4.1 This test method provides a means of establishing
the source and receptor shall be as indicated in Table 1 (see
specular gloss limits for bright, semi-mat, and mat glazed
also Test Method D523). The angular dimensions of the
surfaces. It is realized that specular gloss measurements do not
receptor field stop are measured from the receptor lens in a
always correlate well with visual rankings of glossiness be-
collimated-beam type instrument, and from the test surface in
cause specular gloss is only one of several related appearance
a converging-beam type instrument. See Fig. 1 for a general-
attributes that produce the sensation of gloss. However, the
ized illustration of the dimensions. The tolerances are chosen
prescribedtestmethodisofsufficientaccuracyfortheintended
so that errors of no more than one gloss unit at any point on the
purpose.
scale will result from errors in the source and receptor
apertures.
5.3 Vignetting—There shall be no vignetting of rays that lie
ThistestmethodisunderthejurisdictionofASTMCommitteeC21onCeramic within the field angles specified in 5.2.
Whitewares and Related Products and is the direct responsibility of Subcommittee
5.4 Spectral Conditions—Results should not differ signifi-
C21.03 on Methods for Whitewares and Environmental Concerns.
Current edition approved July 1, 2016. Published July 2016. Originally approved cantly from those obtained with a source-filter photocell
in 1965. Last previous edition approved in 2011 as C584 – 81 (2011). DOI:
combination that is spectrally corrected to yield CIE luminous
10.1520/C0584–81R16.
efficiency with CIE Source C. Since specular reflection is, in
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. DOI: 10.1520/C0584-81R06. For more complete data see Hammond III, H. K., and Nimeroff, I.,“ Measure-
See Illing, A. M., “Comparison of Instrument Measurement and Visual mentofSixty-DegreeSpecularGloss,” Journal of Research,Nat.BureauStandards,
Estimation of Specular Gloss of Glazed Ceramic Tile,” Materials Research & Vol 44, June 1950 ( RP 2105): also Hunter, R. S., “Gloss Evaluation of Materials,”
Standards, Vol 2, No. 2, Feb. 1962, p. 117. ASTM Bulletin, No. 186, December 1962.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C584 − 81 (2016)
TABLE 1 Angles and Relative Dimensions of Source Image and Receptors
In Plane of Measurement Perpendicular to Plane of Measurement
Relative Relative
θ, deg 2 tan θ/2 θ, deg 2 tan θ/2
Dimension Dimension
A
Source image tolerance ± 0.75 0.0131 0.171 3.0 0.0524 0.682
0.25 0.0044 0.057
60° receptor tolerance ± 4.4 0.0768 1.000 11.7 0.2049 2.668
0.1 0.0018 0.023 0.2 0.0035 0.046
A
Maximum; no minimum specification.
FIG. 1 Generalized Glossmeter Showing Apertures and Source Image F
...