Overview
ISO 8604:1988 is an international, bilingual (English/French) standard that establishes a common vocabulary and symbol system for crosslinkable prepregs (pre-impregnated reinforcement and resin systems). Published as the first edition in 1988 and prepared by ISO/TC 61 (Plastics), the standard defines 36 terms and 25 letter symbols used in the designation, production and use of thermosetting prepregs.
The standard covers terminology for raw materials, prepreg product types, and special grades. It also provides letter symbols that specifically designate product type, resin type, reinforcement type, reinforcement form and reinforcement orientation. The first occurrence of each symbol in text should be shown in parentheses and preceded by the full term.
Key Topics
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Scope and bilingual definitions: Terms and symbols provided in both English and French for consistent international use.
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Terms covered: 36 defined terms (examples include prepreg, resin matrix, reinforcement, additive, filler, thickening agent) that align with ISO 472 (Plastics - Vocabulary).
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Symbols: 25 letter symbols for concise product designation. Examples from the standard:
- Product type: PIR (pre-impregnated roving), PIF (pre-impregnated fabric), PIM (pre-impregnated mat), UD (uni-directional prepreg), SMC, TMC, BMC, DMC
- Resin type: EP (epoxy), PUR (polyurethane), PF (phenolic), UP (unsaturated polyester), VE (vinyl ester)
- Reinforcement type: G (glass), C (carbon), A (aramid)
- Reinforcement form: C (chopped strand), F (woven fabric), M (continuous filament mat), R (roving), S (staple fibre), U (uni-directional fabric)
- Orientation: C (continuous), D (directional), R (random)
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Grades and applications: The standard describes grade qualifiers based on shrinkage behaviour (general purpose, low shrink, very low shrink, zero shrink) and application-focused qualifiers (electrical, corrosion-resistant, food contact, improved fire behaviour).
Applications
ISO 8604:1988 provides practical value to organizations involved in composite materials and prepreg manufacturing by enabling:
- Consistent product designation across suppliers and international markets
- Clear specification and procurement of resin and reinforcement combinations
- Improved quality assurance and traceability through standard symbols on labels, drawings and material data sheets
- Better communication between engineers, manufacturers, regulatory bodies and buyers in sectors such as aerospace, automotive, electrical, marine and industrial composites
Related Standards
- ISO 472:1988 - Plastics - Vocabulary (normative reference cited by ISO 8604)
- ISO/TC 61 (Plastics) is the responsible technical committee for the development of this standard.
For implementation, reference the bilingual definitions and symbol tables within ISO 8604:1988 to ensure accurate, standardised labelling and documentation of prepreg products in design, production and procurement workflows.
