Overview - ISO 13632:2012 (Rosin sampling and colour measurement)
ISO 13632:2012 specifies standardized procedures for sampling and sample preparation of rosin and rosin derivatives to ensure reliable colour measurement for use in paints and varnishes. The standard covers sampling from drums, molten/liquid rosin, and solid forms (flakes, pellets, pastilles) and describes how to prepare samples for measurement either as neat rosin or as rosin in solution. The actual colour measurement methods are referenced to other standards (e.g., ISO 4630 and ASTM D509). Annex A provides a correlation between the Gardner and USDA colour scales.
Key topics and technical requirements
- Sample form and cleanliness: Use freshly broken lumps free of dust and fine particles.
- Melting and handling:
- Melt in a clean container (oven, hotplate, heat gun, sand or oil bath) in an inert-gas atmosphere.
- Avoid overheating and avoid bubble formation by stirring slowly.
- Time from start of heating to pouring must not exceed 15 minutes.
- Neat rosin measurement (Gardner):
- Pour molten rosin into a test tube or cuvette while molten and measure immediately using ISO 4630-1 or ISO 4630-2 procedures.
- Rosin in solution (Gardner):
- Prepare a 50.0:50.0 (by mass) solution in analytical-grade toluene, dissolve at room temperature, then measure.
- USDA method:
- Pour molten rosin into a mould giving a 22.2 mm viewing path (cube) before measurement per ASTM D509.
- Reporting: Test reports must state the method of sample preparation in addition to measurement results.
- Scale correlation: Annex A details how to correlate USDA and Gardner scales (includes CIE x,y,Y data, use of Beer’s law for path-length correction and ΔE comparisons).
Practical applications and users
ISO 13632 is intended for:
- Quality control laboratories in rosin production and resin processing
- Manufacturers and formulators of paints, varnishes, adhesives, inks and related binders
- Third-party test labs and QA teams evaluating incoming raw materials
- Procurement and specification writers who require traceable, comparable colour data for rosin grades
Benefits include consistent sampling practice, repeatable colour measurement, and reliable comparisons between Gardner and USDA colour values.
Related standards (key references)
- ISO 4630-1: Gardner colour scale - visual method
- ISO 4630-2: Gardner colour scale - spectrophotometric method
- ASTM D509: Colour and sampling procedures for rosin (USDA scale)
Keywords: rosin sampling, colour measurement, Gardner scale, USDA scale, paint binders, rosin in solution, toluene, ISO 13632.
Open preview (PDF)Binders for paints and varnishes — Rosin — Sampling and sample preparation for colour measurement