Ink selection: The following factors are considered when choosing gravure inks for heat shrinkable labels.
1. Drying performance of ink
When printing shrink film, the printing speed is slow, the drying temperature is low, and the substrate is easily eroded by solvents, so special attention should be paid to selecting inks with better solvent release and anti-offset.
2. Shrinkage performance of ink
The shrinkage performance of the ink must match the shrinkage characteristics of the shrink film. If a low shrinkage ink is used on a film with a high shrinkage rate, the ink layer will burst.
3. Content resistance
Although the ink will be considered and tested for the corresponding acid resistance, alkali resistance and alcohol resistance in the formulation design and production process, but because the application range of shrink labels is very wide, the content is very different, before use, especially for printing When labeling daily chemical products and medicine bottles, it is necessary to do a test first to confirm the resistance of the ink. Gravure Ink
4. Printing substrate
There are not many general-purpose inks such as DIC MSR, so special attention should be paid to the substrate used when selecting inks, otherwise problems such as low ink adhesion will be caused due to improper selection. What’s more, if the benzene-containing ketone-containing ink suitable for printing PVC film is mistakenly used to print the OPS film, the OPS film will dissolve, the ink transfer will be poor, and sometimes the film will break under the action of printing tension.
5. Conventional indicators of ink
It mainly includes indicators such as printability, adhesion, abrasion resistance, scratch resistance and rub resistance of the ink. The shrinkage ink is no longer compounded after printing, so the requirements for these indicators are higher than that of the general compounded ink, especially the slipperiness of the ink, which determines the slippage efficiency of the printed label on the surface of the container. Improper design will cause sleeve labels. Failures such as inefficiency and uneven shrinkage.