Overview
ISO 2078:2022 - "Textile glass - Yarns - Designation" specifies a standardized system for designating textile glass yarns (including single, multiple-wound, folded/plied, cabled, textured yarns, strands, slivers and rovings) using their linear density expressed in the tex system. The standard provides a concise, machine-readable and human-readable naming convention that helps manufacturers, specifiers and buyers identify yarn composition and construction consistently.
Key topics and requirements
- Scope: Applies to textile glass yarn designation, aligning with ISO rules for yarn naming (see ISO 1139).
- Core designation elements:
- Type of glass (single-letter codes such as E, D, A, C, S, R, AR, E‑CR, Q, QB, BF) indicating glass chemistry and general properties (e.g., electrical, chemical resistance, high silica).
- Type of yarn letter (C = continuous, D = discontinuous, B = binary/composite).
- Nominal fibre/filament diameter (1–2 digits in micrometres).
- Linear density preferably expressed in tex (unit may be omitted when tex is used).
- Twist direction and twist value (turns per metre) when applicable.
- Number of constituents for plied, cabled or assembled yarns.
- Optional manufacturer code to record additional information (sizing, finish, total linear density).
- Designation formats for different constructions:
- Base yarns and tapes (e.g., EC10 40)
- Simple yarns, textured yarns (e.g., EC9 34 Z 40; EC9 340 T352)
- Plied/retwisted yarns, cabled yarns and assembled yarns with rules for simplified or full notations (examples: EC9 34 Z 150 × 2 S 100 × 3 Z 80)
- Stratifil (global linear density for rovings/strands, e.g., EC10 2400)
- Referenced standards: ISO 1139 (yarn designation rules), ISO 2 (twist indication), ISO 472 (vocabulary).
Applications and users
Practical uses of ISO 2078:2022 include:
- Specification and procurement of glass yarns for composites, reinforcement fabrics, laminates, and technical textiles.
- Quality control and traceability in manufacturing, ensuring consistent material identification across suppliers.
- Product datasheets, test labs and certification bodies requiring unambiguous yarn descriptions.
- R&D and material selection for engineers designing fiber-reinforced components.
Who uses it:
- Glass yarn and fibre manufacturers
- Composite and textile fabricators
- Material engineers, procurement specialists and standards writers
- Test laboratories and quality assurance teams
Related standards
- ISO 1139 - Textiles: general rules for yarn designation
- ISO 2 - Indication of twist direction
- ISO 472 - Plastics vocabulary (relevant terms)
ISO 2078:2022 enables clear, consistent identification of textile glass yarn properties (glass type, construction, linear density and twist), improving specification accuracy and supply-chain communication for industries using glass fibre reinforcement.
