This document discusses tests to evaluate the curing of UV inks and varnishes. Ethanol is used to test the curing of UV inks by applying it to printed samples with cotton and observing how many rubs it takes for the ink to deteriorate or be destroyed. Methyl ethyl ketone (MEK) is used similarly to test the curing of UV varnishes. The test results depend on factors like the size and amount of solvent used, pressure applied, and speed of rubbing. MEK is more aggressive so it is only used to test varnishes. A test showing lack of cure could also be due to insufficient varnish coating weight.

1. CURE &
PERFORMANC
E ASSESMENT

2. Solvent resistance tests
These are designed to check the curing of UV inks and varnishes.
Ethanol is used for testing the cure of UV inks; while Methyl Ethyl Ketone (M.E.K.) is used to test the curing of UV
varnishes.
Ethanol resistance test.
Principle:
Ethanol has a dissolving action, especially on the non-reacted components of the ink.
Operation mode:
• Soak cotton (or similar) with ethanol. Then place the cotton on the face of the print sample and rub backwards
and forwards at constant pressure and at regular speed and amplitude.

3. • Count the necessary numbers of cycles needed to register.
• the beginning ofthe ink film deterioration,
• the complete destruction of the ink film.
The results of the test will depend on:
• the size of the cotton pad,
• quantity of solvent used,
• exerted pressure,
• deplacement speed on the print sample,
• ambient temperature (solvent evaporation).
MEK resistance test:
Like Ethanol, MEK has a dissolving power action on varnishes, especially on its nonreacted components. MEK
is used to test the curing of UV varnishes only, since it would be too aggressive on UV inks (a test using MEK
would not give conclusive results on UV inks). Refer to the Ethanol resistance test for the application mode.
It must be noted that a negative test result can not only be due to a lack of cure, but also due to an insufficient
varnish coating weight.

6. Source:
1. https://printcolormanagement.wordpress.com/2012/10/03/tests-to-check-the-degree-of-uv-curing-printing/
2. https://www.slideshare.net/ronakjoshi/uv-ink
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Author :
Sugeng Endarsiwi is registered Professional Engineer (IPP) at The Indonesia Engineer Institution (PII). 20 years
experience in Printing Ink Manufacturer in Southeast Asia (SEA). Started Polymer Base Ink (UV Cured Ink) in
Vietnam to made UV OPV and UV Offset Ink for Packaging (Offset Printing on Heidelberg and Mitsubishi Offset
Printing Machine.
Graduated from Executive MBA form JUC Malaysia (2022), focused on Business Strategy and Management
Projects.