ISO 1139:1973

Overview

ISO 1139:1973, titled Textiles - Designation of yarns, is an international standard established by the International Organization for Standardization (ISO). It defines standardized methods for the designation and notation of yarns across the textile industry. The standard focuses on describing yarn composition-whether single, folded, cabled, or multiple wound-using a consistent system based primarily on linear density measured in the Tex System. It covers key characteristics such as the number of filaments, direction and amount of twist, and the number of yarn folds, providing clear and concise notations for yarn identification and classification.

This standard applies broadly to all conventional yarn types except for special yarns like fancy yarns, bulked yarns, textured yarns, or yarns created by wrapping a core with textile or non-textile materials. ISO 1139 aids communication between manufacturers, buyers, and testers by standardizing yarn descriptors to improve clarity and precision in textile production and trade.

Key Topics

• Yarn Types Defined

  • Single yarns (spun, monofilament, multifilament)
  • Folded yarns (twofold, multifold)
  • Cabled yarns
  • Multiple wound yarns

• Yarn Notation Methods

  • Single-to-fold notation: Starts from the linear density of the single yarn; uses the multiplication sign (X) to indicate folds.
  • Fold-to-single notation: Starts from the resultant yarn’s linear density; uses the solidus (/) to separate components.

• Yarn Characteristics Included in Notation

  • Linear density expressed in Tex
  • Number of filaments in filament yarns
  • Direction and amount of twist
  • Number of folds or cables

• Terminology and Symbols

  • Symbols such as “R” for resultant linear density, “f” for filaments, and “t₀” for zero twist
  • Directions of twist designated by ISO 2 symbols (Z or S)

• Nominal vs. Actual Values

  • Nominal values indicate general, agreed-upon characteristic values for standard communication.
  • Actual values represent measured data from authorized testing procedures.

Applications

ISO 1139:1973 provides essential guidance for textile manufacturers, quality control laboratories, and industry professionals who need accurate and standardized yarn descriptions. Its practical applications include:

• Yarn Specification and Ordering: Enables clear communication between manufacturers and buyers by providing unambiguous yarn descriptions.
• Quality Control and Testing: Facilitates reproducible reporting of yarn characteristics and analysis results.
• Production Planning: Helps in calculating manufacturing parameters based on yarn linear density and twist.
• Research and Development: Assists in documenting yarn construction details for innovation and product development.
• International Trade: Standardizes yarn designation to ease global commerce and reduce disputes related to product specifications.

The system allows for abbreviated notations omitting less critical details when appropriate, improving efficiency without sacrificing clarity.

Related Standards

• ISO 1144: Textiles – Universal system for designating linear density (Tex System), which complements ISO 1139 by defining the linear density units.
• ISO 2: Textiles – Designation of the direction of twist in yarns and related products, providing standard symbols for twist direction.
• ISO 858: Netting yarns for fishing nets – Designation in the Tex System, using single-to-fold notation similar to ISO 1139 but tailored for netting yarns.
• ISO 2947: Textiles – Integrated conversion table for replacing traditional yarn numbers by rounded values in the Tex System, facilitating smooth transition to ISO 1139 notation.

Together these standards form a coherent framework improving textile yarn identification, measurement, and communication worldwide.

Keywords: ISO 1139, yarn designation, textile standards, Tex System, linear density, yarn notation, folded yarns, cabled yarns, yarn twist, filament yarn, textile industry standard, yarn classification, yarn specification, international textile standards