Significance and Use
Oversize particles in a printing ink may damage a printing plate, plug a cell, clog a nozzle and adversely affect the appearance of printed ink films. Fineness of grind measurements are useful for deciding when to stop the dispersion process and for determining if the test material meets specifications as agreed upon between the supplier and the customer.
1.1 This test method describes the procedure for determining the fineness of grind of printing inks using a NPIRI Grindometer. It evaluates the size of the largest particles in a finished dispersion but not average particle size or concentration of sizes.
1.2 This test method covers both manual and automatic drawdowns using an A1 scraper.
1.3 This test method is applicable to any dispersion that is fine enough to fall within the 0–25 μm range of the specified grind gauge. With a minor variation in procedure, it is applicable to both paste (nonvolatile) and liquid (volatile) inks.
Note 1—The 0–25 μm gauge specified in this test method is similar in principle to the 0–100 μm Hegman gauge described in Test Method D1210 and the various gauges described in ISO 1524:2000. Sieve analysis for concentration of particles above 45 μm is covered in Test Method D2067.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D1210 Test Method for Fineness of Dispersion of Pigment-Vehicle Systems by Hegman-Type Gage
D2067 Test Method for Coarse Particles in Printing Ink Dispersions
D6846 Practice for Preparing Prints of Paste Printing Inks with a Printing Gage
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
ISO1524:2000 Paints, varnishes and printing inks -- Determination of fineness of grind
A1 Scraper; Automatic Drawdown Machine (ADM-1); degree of dispersion; grind gauge; NPIRI Grindometer; pigment dispersions; printing inks; Dispersion; Fineness of grind (dispersion); Grinding materials/operations; NPIRI grindometer; Pigment dispersion (paints/related coatings/materials); Pigments (general properties); Printing inks/vehicles;
ICS Number Code 87.080 (Inks. Printing inks)
ASTM International is a member of CrossRef.
Citing ASTM Standards
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