ISO 3262-15:2023

Overview

ISO 3262-15:2023 is an international standard that specifies the requirements and test methods for vitreous silica used as an extender. Vitreous silica is a non-crystalline form of silica supplied as a powdered material and comes in two grades: Grade A (quartz glass) and Grade B (fused silica). This standard is essential for quality control, ensuring the material meets defined chemical and physical characteristics to suit its application in coatings, paints, and other industrial products.

Key Topics

• Scope and Definitions: Defines vitreous silica and distinguishes between Grade A (transparent quartz glass) and Grade B (opaque fused silica).
• Essential Requirements:
  • Silica Content: Minimum 99.5% for Grade A, 99% for Grade B.
  • Quartz and Cristobalite Content: Limits set to control crystalline phases that might affect performance.
  • Matter Volatile at 105 °C: Specifies maximum limits to control impurities and moisture.
  • Loss on Ignition, pH, and Water Soluble Matter: Additional compositional parameters to ensure material consistency.
• Conditional Requirements: Include particle size distribution, residue on sieves, color, lightness, resistivity of aqueous extract, and oil absorption value-tested as per agreement between suppliers and users.
• Sampling and Testing Methods:
  • Sampling follows ISO 15528 to ensure representative samples.
  • Silica content is determined through precise gravimetric methods involving sulfuric acid and hydrofluoric acid treatment, muffle furnace ignition, and weighing with high accuracy.
  • Test methods also reference multiple ISO standards such as ISO 787 series for pigment and extender testing and ISO 8130-13 for laser diffraction particle sizing.
• Reporting: Test reports must document product identification, test results, compliance status, deviations, any anomalies, and test date for traceability and quality assurance.

Applications

Vitreous silica as defined in ISO 3262-15:2023 is widely used as an extender in:

• Paints and Coatings: Improves durability, opacity, and texture.
• Plastics and Rubber: Enhances thermal resistance and mechanical properties.
• Electronics and Optics: In forms where high purity and controlled particle size are critical.
• Cosmetics and Pharmaceuticals: As an inert carrier to adjust consistency and performance.
  Standardized testing and specification compliance ensure reliable performance across these sectors, contributing to enhanced product quality and safety.

Related Standards

• ISO 3262 Series: General series covering extenders with Part 1 detailing introduction and general test methods.
• ISO 787 Series: General methods of test for pigments and extenders, including tests for volatile matter, pH, oil absorption, and water solubility.
• ISO 8130-13: Particle size analysis by laser diffraction, relevant for conditional requirements in particle size distribution.
• ISO 15528: Guidelines for sampling paints, varnishes, and raw materials ensuring sample representativity.
• ISO 3696: Water purity requirements for analytical laboratory use.
• ISO 18451-1: Terminologies related to pigments, dyestuffs, and extenders to unify language and definitions.

Adhering to ISO 3262-15:2023 supports manufacturers and users in achieving consistent quality and compliance for vitreous silica extenders, facilitating international trade and application performance. For further implementation guidance, consult the ISO website or the national standards bodies.