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					                                                                                                     IGT Information leaflet W50
                                                                                                               IGT AIC2-5T2000
                                                                                                                  2
                                                                                              INK TRANSFER in g/m (85 Shore A)
                                                                                                                     Version : October 2003

Introduction:                                                             Materials / testing conditions
Most printability tests are performed on the base of known ink            1 IGT AIC2-5T2000                               710
film thickness on the printing form (printing disc). In some cases,       2 IGT High Speed Inking Unit 4                  466.410.100
for instance the determination of the ink consumption, it is              3 (with 4 segmented top roller for              (466.003.003)
necessary to measure the ink transfer in g/m2 on the paper. Direct           conventional inks)
measurement on the printed paper is not possible. For that reason         4 IGT ink pipette                               408.200 or 408.400
the ink transfer is calculated in g/m2 from the difference in             5 Printing disc, with rubber 85 Shore A,        402.333
weight of the printing form before and after printing and the sizes          coated, 50 mm
of the print.                                                             6 Strips of Ka APCOO II/II paper,               404.009.025
The test is described for an ink to be tested on a standard paper.           340 x 55 mm,
Of course the investigation can be made with a standard ink on a
paper to be tested as well.                                               7    Ink to be tested
                                                                          8    If desired, strips of paper to be tested,
The following listing shows the different methods, dependent to                preferable 55 x 340 mm, 3 strips per
the roughness of the paper used:                                               sample
W50      rubber 85 Shore A for very smooth papers                         9 Lint free rags
W72      rubber 65 Shore A for smooth/rough papers                        10 Cleaning naphtha
W80      rubber blanket for very rough papers                             11 Presicion scale, accuracy 0.1 mg or
W81      aluminium for letterpress                                             better
All these tests have been described with the printing forms for           Printing force                            625 N
conventional offset inks. For UV-inks the alternative printing            Printing speed                            0.2 m/s
forms and top roller for the inking unit are mentioned in the notes       Ink film thickness                        2.4 or 4.8 µm
of the W-leaflets.                                                        The numbers 1 thru 6 are available at IGT Testing Systems.
                                                                          The numbers 5 thru 6 are available as Ink Transfer Set Rubber
Principle:                                                                Disc 85 Shore A for AIC2-5T2000, article number ……
The paper strip is printed with an ink on the printability tester.
Before and after printing the printing form (disc) is weighed on a        2.    Place the printing disc on the printing disc shaft of the
precision scale with an accuracy of 0.1 mg or better. From these                inking unit and ink the disc during the preset time.
weights and the sizes of the print the ink transfer as g/m2 can be        3.    Mount a test strip on the sector of the printability tester.
calculated.                                                               4.    Remove the disc from the inking unit and place it on the
After drying the ink the printed samples can be used for further                precision scale. Note the weight of the disc with the ink in
determination of dry properties as e.g. colour measurement,                     0.1 mg or better (weight = G1 g).
abrasion resistance, chemical resistance, and so on.                      5.    Take the disc from the precision scale and place it on the
                                                                                top shaft of the printability tester.
Method of operation:                                                      6.    Turn the sector into starting position.
• It is recommended to execute the test in the standard                   7.    Press one of the side buttons to start the motor.
atmosphere; to most standards it is 23.0 ± 1.0 °C (73.4 ± 1.8 °F)         8.    Move the printing disc into printing position against the test
and 50 ± 2% rh.                                                                 strip.
• For the operation of the AIC2-5T2000, the High Speed Inking             9.    Press the other side button as well to make a print.
Unit 4 and the ink pipette follow the instructions of the manuals,        10.   After the sector has stopped, release the side buttons.
IGT information leaflet W100 and the displays accurately.                 11.   Move the printing disc out of printing position
• Handle the samples carefully.                                           12.   Take off the printing disc from the shaft and place it on the
                                                                                precision scale. Note the weight of the disc with the ink in
Preparation                                                                     0.1 mg or better (weight = G2 g).
1. Condition the papers, the ink and equipment during > 6                 13.   Clean the printing disc with rags and naphtha.
    hours in the standard atmosphere.                                     14.   Remove the printed strip from the sector.
2. Cut the paper strips (preferable 55 x 340 mm, 3 strips per             15.   Measure the length (L) and the width (W) of the print in cm.
    sample) and mark them with top and/or bottom side,                    16.   Calculate the ink transfer as described in the chapter
    machine and/or cross direction and a code for the type of                   “Assessment”.
    material.                                                             17.   Clean the rollers of the inking unit or use the next segment
3. Adjust the printing force of the upper printing disc shaft to                for the following test.
    625 N and pay attention for the right backlash. See W100.             18.   Repeat the points 1 thru 17 for the next test. It is
4. Adjust the speed to constant (5), end speed 0.2 m/s.                         recommended to perform the test at least three times.
5. Check and if needed, move the slide in front of the sector             19.   After finishing the tests clean and store all parts as described
    into the constant speed mode (5).                                           in the manuals.
6. Check the functioning of the Global Standard Tester                    20.   Make an accurate record of the conditions and the results of
    following the instructions in the chapter “Execution”.                      the test.
7. Fill the ink pipette with the ink to be used.
8. Adjust the High Speed Inking Unit with the settings                    Assessment
    mentioned in note 2.                                                  1. Calculate the ink transfer with the formula:
9. Check the functioning of the High Speed Inking Unit.

Execution
1. Apply 2.4 or 4.8 µm of ink to the inking unit and distribute
    the ink. (indication: 2.4 µm for art paper and 4.8 µm for
    rough paper). See note 3 or the manual of the inking unit.

                               IGT Testing Systems, P.O.Box 12688, 1100 AR Amsterdam, The Netherlands
                                         Keienbergweg 25, 1101 EX Amsterdam, The Netherlands
                         Phone +31 (0)20 409 9300, Fax +31 (0)20 697 4842, E-mail: info@igt.nl Internet: www.igt.nl
                                    W50 for IGT AIC2-5T2000

1.   Calculate the ink transfer with the formula:

                   10,000
     Ink transfer = ---------- x (G1 – G2)
                    LxW
     Here in is:
     L = length of the print in cm
     W = width of the print in cm
     G1 = weight in g of printing disc with ink before printing
     G2 = weight in g of printing disc with ink after printing

2.   Calculate the average and if desired, the standard deviation.
     Sometimes it can be useful to mention the highest and
     lowest values as well.

Notes:
1. The test results of the AIC2-5T2000, AIC2-5 and Global
    Standard Testers 2, 3 and 3H compare well with another on
    the condition that the tests have been carried out under the
    same testing conditions.

2.   It is advised to use the following settings for the High Speed
     Inking Unit 4:
     Water bath                 : 23.0º C (73.4º F)
     Mode                       :2
     Starting time              :5s
     Distribution time          : 10 s
     Distribution speed         : 1.2 m/s
     Inking time printing disc: 5 s

3.   To reach an ink film thickness of 2.4 µm on the High Speed
     Inking Unit 4 with a 4-segmented top roller a quantity of
     0.104 cm³ has to be applied, for 4.8 µm the quantity is 0.208
     cm3. It is not advised to add some ink after a test.

4.   To test UV-inks the printing disc and the top roller of the
     inking unit have to be changed into the following items and
     a UV-dryer has to be used:
     * 402.090 printing disc with rubber 65 Shore A for UV inks,
     50 mm wide, see W72 (rubber for UV 85 Shore A is not
     available)
     * 466.003.009 top roller for UV-inks
     * It is strongly recommended to dry the printed sample
     directly after printing with a UV-dryer.




                                                                          This information leaflet has been compiled with the utmost care.
                                                                          However, may you find any inadequacies or if there are any comments,
                                                                          we kindly request you to send these to IGT Testing Systems, Sales
                                                                          Department.



                               IGT Testing Systems, P.O.Box 12688, 1100 AR Amsterdam, The Netherlands
                                         Keienbergweg 25, 1101 EX Amsterdam, The Netherlands
                         Phone +31 (0)20 409 9300, Fax +31 (0)20 697 4842, E-mail: info@igt.nl Internet: www.igt.nl

				
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posted:5/10/2014
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