Quality Control Testing for Printing Inks

Quality Control testing for printing inks evaluates the physical, chemical, rheological, colorimetric, and performance properties of inks, substrates, and finished printed products against established specifications. Testing may be performed during ink production, prior to press operation, and on the finished printed product to verify conformance with process, stakeholder, and customer requirements. ASTM test methods provide standardized procedures for measuring properties such as viscosity, pigment dispersion, surface wetting, gloss, color difference (ΔE), coefficient of friction, abrasion resistance, drying or cure, chemical resistance, and printed-product performance.

                                                                                                                                          ASTM Test Methods for Printing Inks

1. ASTM D523 — Standard Test Method for Specular Gloss: Measures the specular gloss of a printed or coated surface and provides a quantitative assessment of surface appearance.

2. ASTM D1316 — Standard Test Method for Fineness of Grind of Printing Inks by the NPIRI Grindometer: Measures the largest particles present in an ink dispersion and is used to evaluate pigment dispersion and grind quality.

3. ASTM D1894 — Standard Test Method for Static and Kinetic Coefficients of Friction of Plastic Film and Sheeting: Measures static and kinetic coefficients of friction to evaluate the slip and frictional properties of printed or coated film surfaces.

4. ASTM D2244 — Standard Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color Coordinates: Evaluates color differences between a reference standard and test sample using instrumentally measured CIE color coordinates. Color differences may be expressed using CIELAB (L*, a*, b*), CIE94, CMC, or CIEDE2000 (ΔE₀₀) calculations to establish and evaluate production color tolerances.

5. ASTM D2578 — Standard Test Method for Wetting Tension of Polyethylene and Polypropylene Films: Evaluates the wetting tension of polymer film surfaces using test liquids of known surface tension and can be used to assess surface treatment prior to printing or coating.

6. ASTM D3424 — Standard Practice for Evaluating the Relative Lightfastness and Weatherability of Printed Matter: Evaluates changes in printed materials resulting from exposure to light and weathering conditions.

7. ASTM D4212 — Standard Test Method for Viscosity by Dip-Type Viscosity Cups: Measures the viscosity of liquid inks and related materials for process and formulation control.

8.  ASTM D5264 — Standard Practice for Abrasion Resistance of Printed Materials by the Sutherland Rub Tester: Evaluates the abrasion and scuff resistance of printed inks, coatings, and printed substrates under controlled laboratory conditions.

9. ASTM D5909 — Standard Test Method for Drying Time of Oxidative-Drying Printing Inks by Squalene Resistance: Evaluates the drying characteristics of oxidative-drying printing inks.

10. ASTM D6688 — Standard Practice for Relative Resistance of Printed Matter to Liquid Chemicals by a Sandwich Method: Evaluates the resistance of printed materials to specified liquid chemicals.

11. ASTM D7244 — Standard Test Method for Relative Cure of Energy-Cured Inks and Coatings: Evaluates the relative degree of cure of energy-cured printing inks and coatings.

12. ASTM D7305 — Standard Test Method for Reflection Density of Printed Matter: Measures the reflection density of printed materials for evaluation of printed ink and color performance.

                                                                                                                                             ASTM Test Methods for Packaging

Quality Control testing for packaging evaluates packaging materials, printed surfaces, seals, and completed packages against established performance specifications. Testing may include surface properties, coefficient of friction, print abrasion resistance, seal strength, package integrity, compression, vibration, and drop resistance to determine conformance with stakeholder and customer requirements throughout production and distribution.

1. ASTM D642 — Compressive Resistance: Evaluates the ability of shipping containers and packaging systems to withstand compressive loads associated with stacking, storage, and distribution.

2. ASTM D1894 — Static and Kinetic Coefficients of Friction: Measures the frictional properties of plastic films and packaging surfaces relevant to handling, converting, and packaging operations.

3. ASTM D2578 — Wetting Tension: Evaluates the surface wetting characteristics of polyethylene and polypropylene films used for printing, coating, laminating, and adhesive applications.

4. ASTM D3078 — Leak Testing by Bubble Emission: Detects gross leaks in flexible packaging using internal pressure and bubble emission.

5. ASTM D4169 — Performance Testing of Shipping Containers and Systems: Evaluates packaged products under laboratory simulations of handling, stacking, vibration, impact, and other distribution hazards.

6. ASTM D4728 — Random Vibration Testing: Evaluates shipping containers and packaged products under random vibration representative of transportation conditions.

7. ASTM D5264 — Sutherland Rub Test: Evaluates abrasion and scuff resistance of printed packaging, inks, coatings, labels, and substrates.

8. ASTM D5276 — Drop Test: Evaluates loaded containers and packaged products for resistance to impacts resulting from free-fall drops.

9. ASTM F88/F88M — Seal Strength: Measures the force required to separate seals in flexible barrier packaging.

10. ASTM F2096 — Gross Leak Detection by Internal Pressurization: Detects gross leaks in packaging by internal pressurization and bubble emission.

Introduction to Lithography

How Offset (lithographic) Printing Works