Overview
ASTM D6116-18(2023) is the internationally recognized Standard Test Method for Blocking developed by ASTM International. This standard outlines a precise methodology for determining the resistance of leather materials to blocking under specific laboratory conditions including controlled temperature, humidity, and pressure. Blocking refers to the undesired sticking of leather surfaces, which can compromise leather's appearance and usability, particularly in upholstery and finished leather products. This test method is applicable to most leather types, but explicitly excludes wet blue leathers.
Conforming to SI units and international standardization principles, this test method supports manufacturers, quality assurance professionals, and testing laboratories in verifying leather quality and durability.
Key Topics
- Test Objectives: Measures the ability of leather to resist sticking or adhering when exposed to defined environmental stressors.
- Test Conditions: Specific conditions of temperature (80°C ± 3°C), humidity, and pressure form the basis of this assessment.
- Equipment Requirements: Includes a forced circulating hot air oven, American Medical Museum jar (with lid), petri dish with cover, weights, and a perspirometer.
- Specimen Preparation: Leather samples are cut into standard sizes and tested along both parallel and perpendicular axes to the backbone.
- Test Procedures:
- Method 1 (Petri Dish): Leather specimens are folded and subjected to weighted pressure in a petri dish before examination.
- Method 2 (Perspirometer): Alternative apparatus uses glass plates with controlled compression, simulating application of pressure over time.
- Assessment: After testing, specimens are visually examined for ease of separation, grain damage, and finish peeling. Results are reported as pass or fail based on blocking performance.
- Safety Guidelines: Users are responsible for meeting appropriate safety, health, and environmental protocols.
Applications
The ASTM D6116 test method is critically important for:
- Leather Manufacturers: Assures compliance with quality standards before finished leather moves to market or into production for consumer goods.
- Upholstery Producers: Verifies durability and workability of upholstery leathers, helping prevent product defects stemming from finish adhesion issues.
- Quality Control Laboratories: Provides a standardized, repeatable approach for evaluating batch-to-batch consistency and performance of leather.
- Research & Development: Assists in the development of new leather treatments or finishes with improved anti-blocking characteristics.
- Regulatory Compliance: Supports adherence to globally recognized standardization principles, facilitating international trade and acceptance of test results.
Related Standards
When conducting or referencing the ASTM D6116 test, it may be beneficial to consider other closely associated standards including:
- AATCC TM15 - Standard test method for colorfastness to perspiration, referenced as an alternative apparatus in the D6116 procedure.
- Other ASTM Leather Standards: Such as ASTM D1814 (resistance to cracking) and ASTM D2813 (finish adhesion), which address different aspects of leather quality.
- International Trade Standards: Developed under the WTO TBT Committee guidelines, ensuring relevance and acceptance in global markets.
By adhering to ASTM D6116-18(2023), organizations can demonstrate commitment to high-quality, reliable leather goods, ensuring customer satisfaction and facilitating compliance in both domestic and international supply chains.
Keywords: leather blocking, finish adhesion, ASTM D6116, leather quality testing, upholstery standards, anti-blocking, leather durability, international standards, ASTM International, AATCC TM15