ASTM-D5958:99(R2020) pdf free download – Standard Practices for Preparation of Oil-Based Ink Resin Solutions.
12. Summary of Stirrer/Hot Plate Practice
12.1 Small samples of ink resin and aliphatic ink oil or ink resin and alkali-refined linseed oil (ARLO) are cut into dispersion in an Erlenmeyer flask to a specific temperature, at a specified rate, with stirring.
12.2 The resulting fluid dispersion can he used to measure parameters such as viscosity and aliphatic soluhility or compatibility of a printing ink resin.
13. Apparatus
13.1 Erlenn,ever Flask, l25-mL, fitting the following descnption: a height of 114 mL, an outside base diameter of 67 mL. and an opening of 27 mL.
13.2 Magnetic Stirring Bai; polytetrafluoroethylene-coated. and 25 mm in length.
13.3 Thermometer, capable of reading 0 w 250°C and conforming to Specification El. Alternately, temperature measuring devices such as liquid-in-glass thermometers, thermistors, thermocouples. or platinum resistance thermometers that provide equivalent or better accuracy and precision, that cover the temperature range specified. may he used.
13.4 Cork Stopper, high quality, designed to fit the flask used. This cork is then bored out appropriately to receive the thermometer in 13.3 in a snug fashion. The hole should be drilled at an angle of approximately 25° so the tip of the thermometer comes to rest at the inside edge of the flask. Place a small groove on the side of the cork to prevent pressure build – up.
13.5 Hot Plate Stirrer, capable of a surface temperature of 300°C.
13.6 Stop Watch.
14. Calibration and Standardization
14.1 The setting of the hot plate surface temperature must be calibrated by making a blank run in the following manner.
14.2 Determine the total mass of the intended solution described in 12.1 (Note: the mass should be between 30 and 45
g). Weigh into the 125-mL Erlenmeyer flask a quantity of ARLO equal to the intended solution mass described in 12.2. Next, add the stirring bar and allix the thermometer/cork assembly described in 13.4 to the Erlenmeyer flask.
14.3 Turn on the hot plate temperature controller to a setting that will give a surface temperature of approximately 300°C. Allow the hot plate 10 mm to heat up and equilibrate.
14.4 Set the flask on the preheated hot plate stirrer and begin stirring.
14.5 Start the stop watch.
14.6 Measure the time required for the ARLO to reach a temperature of 215°C.
14.7 The hot plate surface temperature is correct when the ARLO heats from room temperature to 2 15°C in 11 mm ± 15 s. On a hot plate, this is usually at a setting between 5 and 6 on the temperature-controller dial.
15. Procedure
15. 1 Crush large size pieces of resin sample and pass the crushed resin through a 16-mesh sieve.
15.2 Weigh to ±0.02 g into the Erlenmeyer flask, the ink resin and solvent at the ratio agreed upon between producer and user. Typical resin solutions are noted in 9.3.1. The total mass of ink resin solids and solvent should be between 30 and 45g.
15.3 Carefully place the stirring bar into the flask to avoid splashing the solvent.
No-rE I—It is not recommended that the stirring bar he added to the tared flask while on an electronic balance. The magnetic field associated with the stirring bar can atlèc weighing accuracies.
15.4 Aftix the thermometer/cork assembly in the mouth of the flask. Adjust the thermometer tip so it is just oil the bottom surface of the flask.
155 Place the flask on the hot plate stirrer that has been heated 10 mm to the calibrated setting derived in Section 14.
15.6 Without stirring, let the ink resin-solvent slurry heat to 100°C.