ASTM D279-02(2023) PDF

Overview

ASTM D279-02(2023), titled "Standard Test Methods for Bleeding of Pigments," provides established procedures for evaluating the bleeding characteristics of dry pigments used in coatings and other applications. Developed by ASTM International, this standard is vital for ensuring pigment performance in situations where bleed resistance is necessary. The test methods outlined enable rapid, reproducible assessments of pigment bleeding-either from direct solvent contact or through observation of color migration in coated systems.

Key Topics

• Bleeding of Pigments: The standard covers two main test methods to determine pigment bleeding, which refers to the unwanted migration of pigment color into adjacent materials or layers.
• Test Method A – Direct Solvent Contact: In this method, pigment is exposed directly to a solvent (commonly toluene) to quantify the amount of color that bleeds into the solvent. This is a quick, straightforward indicator of general bleeding tendencies.
• Test Method B – White Overstripe of a Pigmented Film: Here, a colored base coat containing the pigment is overcoated with a white film. Observing color migration into the white layer offers a more practical assessment of bleed resistance in real-world applications.
• Visual and Instrumental Assessment: The extent of bleeding is visually rated as none, slight, moderate, or severe, and can be quantitatively measured using color difference methods per ASTM D2244.

Applications

ASTM D279-02(2023) is widely utilized across industries where pigment stability and color integrity are critical, such as:

• Paints and Coatings: Manufacturers assess the suitability of pigments for architectural, automotive, and industrial coatings to prevent color migration that could impact appearance and product quality.
• Inks and Plastics: Ensures that pigments do not bleed into adjacent materials, maintaining sharp definition in printed or molded products.
• Quality Control and Research: Provides a standardized approach for pigment producers, formulators, and end-users to verify and compare bleed resistance among pigment batches or suppliers.
• Specification Compliance: Helps purchasers, specifiers, and regulatory bodies determine if pigment materials meet required bleed resistance standards for specific applications.

Using these ASTM test methods enables companies to:

• Identify pigments with adequate bleed resistance for demanding environments
• Avoid defects caused by color migration
• Document compliance with customer or regulatory requirements
• Streamline development and qualification of new pigment products

Related Standards

For comprehensive pigment evaluation, additional ASTM standards are commonly referenced alongside ASTM D279-02(2023):

• ASTM D2244 – Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color Coordinates
• ASTM D2616 – Test Method for Evaluation of Visual Color Difference with a Gray Scale

These companion standards support accurate color measurement and visual assessment, ensuring robust evaluation of pigment bleeding in line with international best practices.

Keywords: bleeding of pigments, pigment bleeding test, color migration, overstripe, ASTM D279, pigment bleed resistance, pigment evaluation, coating test methods

By adhering to ASTM D279-02(2023), organizations benefit from reliable, standardized techniques to assess and compare the bleeding behavior of pigments in various solvent and coating systems, supporting high-quality results across coatings, plastics, inks, and related industries.