Overview
ISO 22785-6:2026 establishes standardized methods for the stone-chip resistance testing of coatings applied to plastics, plastics composites, and similar substrates. Developed by the International Organization for Standardization (ISO), this standard addresses the unique behaviors exhibited by coatings on plastics during exposure to stone-chip and impact conditions, making it especially relevant to industries where surface durability and quality are paramount.
Stone-chip resistance testing evaluates the capability of paint and varnish coatings to withstand damage from impacts, such as those caused by loose chippings on road surfaces. This standard recognizes the significant differences in substrate behavior between plastics and metallic materials, ensuring that test results are meaningful for plastics and composite applications.
Key Topics
- Testing Scope: Covers coatings on various plastic substrates, emphasizing the effect of the specific substrate on test outcomes.
- Test Methods:
- Stationary Multi-Impact Test (referencing ISO 20567-1): Simulates repeated impacts using iron grit.
- Single-Impact Tests:
- With guided impact body (ISO 20567-2): Generates controlled, repeatable impacts.
- With free-flying impact body (ISO 20567-3): Assesses resistance to a single, unconfined impact event.
- Sample Preparation: Details requirements for preparing and conditioning test samples to ensure reliability and reproducibility, taking into account the unique properties of plastics.
- Influence of Substrate: Highlights that the hardness and flexibility of plastics composites differ from metals, affecting testing outcomes. Results from different plastic types are not comparable.
- Evaluation: Provides guidance for visual assessment and measurement of damage, including techniques to increase contrast for accurate evaluation.
Applications
ISO 22785-6:2026 is applicable across numerous sectors where plastics and composite materials are coated for protection and appearance. Key practical uses include:
- Automotive Industry: Ensures paint and coating reliability for plastic parts such as bumpers, mirror housings, and trim, which are commonly exposed to road debris impacts.
- Consumer Goods: Applies to coated plastic appliances, electronics, and sporting goods, improving product durability and perceived quality.
- Aerospace and Transportation: Protects coated composite components subject to high debris impact environments.
- Quality Control and R&D: Used by manufacturers and testing laboratories to validate and compare the stone-chip resistance performance of new coatings or substrate materials.
By addressing the particular test requirements for plastics, this standard supports enhanced product life cycles, safety, and customer satisfaction through improved surface protection.
Related Standards
ISO 22785-6:2026 is part of a broader suite of international standards focused on coatings on plastics and composites and general stone-chip resistance evaluation. The following standards are directly referenced or related:
- ISO 22785-1: General introduction to coatings on plastics and composites.
- ISO 4618: Paints and varnishes vocabulary, ensuring consistent terminology.
- ISO 1514: Specifies standard panels for testing paints and varnishes.
- ISO 3270: Defines conditioning and testing climates for paints and varnishes.
- ISO 20567 Series:
- ISO 20567-1: Multi-impact testing on coatings.
- ISO 20567-2: Single-impact test with a guided impact body.
- ISO 20567-3: Single-impact test with a free-flying impact body.
- ISO 20567-4: Mobile multi-impact testing on small areas.
For the comprehensive application and comparison of results, practitioners are recommended to consult these related standards as referenced in ISO 22785-6:2026.
Open preview (PDF)Paints and varnishes — Coatings on plastics and composites — Part 6: Stone-chip resistance testing