고무 화학물질에 대한 COA를 읽는 방법

A COA is the document that turns a chemical from an unknown into a specification. Reading one properly takes about two minutes and prevents most receiving problems.

Fields that must be present

• •Product name and grade exactly matching your order.
• •Batch or lot number matching the marking on the packaging.
• •Production date and retest or expiry date.
• •Test items with units, specification limits and actual measured values — a COA that lists only "conforms" for every item is not a COA.
• •Test method reference for each item (ASTM, ISO or GB standard number).
• •Signature or stamp of the responsible quality function.

Fields buyers skip and regret

• •Moisture or heating loss — critical for hygroscopic materials such as silica and some accelerators.
• •Ash content — reveals inorganic loading.
• •Particle size or sieve residue — affects dispersion and dust.
• •Insoluble content for insoluble sulphur grades, which decays in storage.

Cross-checks that catch problems fast

• •Does the batch number on the COA match the drum?
• •Is the production date recent relative to the stated shelf life?
• •Are the measured values all comfortably inside the range, or are several sitting exactly on the limit?
• •Does the test method match the one in your purchase specification?

Ask for the COA before shipment, not after. A supplier who can only produce one after dispatch is telling you something about their quality system. ## Need the documents or today's price? Send us the grade, quantity and destination port — we return a quotation with COA and MSDS attached. Email manager@fipolymer.com or use the inquiry form on this site.