ISO 23900-6:2015

Overview

ISO 23900-6:2015 is an international standard developed by ISO that provides a method to assess the degree of dispersion of colorants and extenders in thermoplastic polymers. This part (Part 6) details dispersion determination using a film test, making it particularly relevant for quality control in the plastics industry. The standard applies to colorants and/or extenders presented as concentrates or compounds and is intended for all polymers commonly processed by extrusion.

By following ISO 23900-6, laboratories and manufacturers can objectively evaluate dispersibility, a critical factor in the appearance and performance of colored plastic products. Proper dispersion ensures uniform color, avoids defects, and leads to improved material properties.

Key Topics

• Scope and Purpose
  The standard specifies how to evaluate dispersibility of colorants and extenders in thermoplastic polymers by forming film samples with extrusion processes.

• Test Methods

  • Preparation of test mixtures with defined ratios of colorant/extender and base polymer
  • Use of extrusion and film formation (blown or cast film units)
  • Implementation of camera-based inspection systems for detecting dispersion quality

• Terms and Definitions
  Includes clarification of crucial terms such as speck, agglomerate, aggregate, and other parameters related to film assessment and image analysis.

• Evaluation Criteria

  • Quantification of specks (particles, agglomerates, aggregates)
  • Statistical analysis of speck size distribution and area ratios
  • Visual representation and automatic image-based evaluation

• Test Reporting

  • Detailed requirements for documenting test conditions, materials, and results
  • Emphasizes traceability and comparability by standardizing reporting practices

Applications

ISO 23900-6:2015 is highly valuable for organizations involved in plastics manufacturing and compounding, including:

• Quality Control
  Ensures consistent color distribution and detection of potential defects before products reach customers.

• Research and Development
  Assists in optimizing formulations of colorant or extender concentrates for better dispersibility.

• Supplier Qualification
  Provides a harmonized approach for suppliers to demonstrate that their concentrates or compounds meet customer requirements for dispersibility.

• Process Optimization
  Enables fine-tuning of extrusion and compounding equipment to reduce defects such as visible specks or uneven coloration in plastic films.

This standard is applicable for a wide range of polymers used in packaging, automotive components, electronics housings, and other extrusion-processed plastic products.

Related Standards

For broader context, ISO 23900-6 is part of a series addressing the methods of dispersion and dispersibility assessment in plastics. Other relevant standards include:

• ISO 23900-1: General introduction to dispersion methods in plastics
• ISO 23900-2 to ISO 23900-5: Methods for measuring coloristic properties and dispersion ease in various polymers using different procedures
• ISO 4618: Paints and varnishes - Terms and definitions
• ISO 21227-1: Evaluation of defects on coated surfaces using optical imaging

Organizations seeking comprehensive quality assurance in colored or filled plastics should consider aligning with the entire ISO 23900 series and referenced terminology standards.

Keywords: ISO 23900-6, dispersibility, pigments, extenders, thermoplastic polymers, film test, colorant dispersion, plastics, extrusion quality, standardization.