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D210-05 – Standard Test Method Technical Guide
🏭 Composition and Properties
This specification covers the pigment commercially known as bone black, ivory black, or drop black. The dry pigment is manufactured by the calcination of bones and must be free from any admixture with other substances. It shall meet the following requirements:
| 📏 Property | 🎯 Requirement |
|---|---|
| Ash (pigment dried at 105°C), max | 88% |
| Ash insoluble in acids, max | 3.0% |
| Coarse particles (total residue retained on a No. 325 sieve), max | 2.0% |
The pigment is also available as an aqueous dispersion. This form is produced by grinding the specified pigment with water, dispersing agent, biocide, fungicide, pH stabilizer, and defoamer using high-speed dispersion equipment. The dispersion must conform to the following composition:
| 📏 Component | ⚡ Percentage |
|---|---|
| Pigment, min | 38% |
| Dispersing agent | 14% |
| Biocide, max | 1% |
| Fungicide, max | 1% |
| pH Stabilizer, max | 1% |
| Defoamer, max | 1% |
| Water | 44% |
💡 Key Insight: The ash content provides a measure of the inorganic matter present. Maintaining ash content below 88% ensures the pigment’s quality and consistency.
⚙️ Test Methods and Sampling
Sampling requires two random samples from different packages for each 500 lb batch. These can be tested separately or blended into a composite sample. The following ASTM test methods are employed:
- Coarse Particles: Performed in accordance with Test Methods D185.
- Pigment and Linseed Oil in Paste in Oil: Evaluated using Test Methods D1208.
- Mass Color and Tinting Strength: Determined by Test Method D387.
The mass color, tint character, and tinting strength when mixed with a white pigment must stay within mutually agreed limits between purchaser and seller. For any test procedures not covered by ASTM methods, agreements between the involved parties shall apply.
⚠️ Caution: Always verify that the test methods used are in line with the latest ASTM standards to maintain compliance and reproducibility.
❓ Frequently Asked Questions
🔍 What is the maximum ash content for dry bone black pigment? The maximum ash content allowed is 88% when the pigment is dried at 105°C.
💡 Can bone black pigment be purchased as an aqueous dispersion? Yes, it can be supplied as an aqueous dispersion with a minimum pigment content of 38%.
⚡ Which test method is used for determining coarse particles? Test Methods D185 is used for assessing coarse particles retained on a No. 325 sieve.
📌 What is the minimum pigment content in the aqueous dispersion? The aqueous dispersion must contain at least 38% pigment.