How to Read APHA Color Specifications for DMA 40%
2026-11-12
China Amines Co., Limited
A certificate of analysis for dimethylamine 40% aqueous solution may include a line marked “Color, APHA.”
That entry provides a measured quality parameter. To use it correctly, buyers need the agreed limit, the test method, and the result for the delivered batch.
Understand what the color requirement describes
APHA color reporting uses the platinum-cobalt color scale to describe light coloration in suitable liquids.
ASTM D1209 covers visual color measurement for essentially light-colored liquids whose color characteristics are suitable for comparison with platinum-cobalt standards. Its scope matters when selecting an appropriate method.
A color result should therefore be read together with the method used to obtain it.
Check the limit for the proposed grade
Eastman’s published DMA 40% sales specification includes a maximum color of 15 APHA, measured using a colorimeter. That requirement applies to the named Eastman grade; your purchase should follow the specification agreed with your supplier.
Distinguish the maximum permitted value from the actual batch result. Record both clearly during incoming review.
Confirm how the measurement was made
Ask whether the reported value comes from a visual comparison or an instrumental method.
Confirm the applicable procedure and reporting conventions before comparing results from different laboratories. A specification that lists “colorimeter” does not, by itself, establish that testing follows ASTM D1209.
For results near an acceptance limit, use the agreed rounding and decision procedure.
Review color alongside other quality results
Color contributes one part of the material assessment. Review it with DMA assay and any agreed impurity limits.
If a batch shows an unexpected color result, retain the batch identification and ask the technical teams to review the evidence. A color value alone cannot identify the cause of a difference or establish the complete composition.
For applications sensitive to color, discuss the requirement during supplier qualification.
Discuss your DMA 40% color requirements
Send China Amines Co., Limited your approved specification, required color limit, test method, quantity, packaging preference, and destination.
Clear requirements help establish a consistent basis for quotation, documentation, and incoming inspection.
Inquiries: info@chinaamines.com