Bottle cap graphic design and printing points analysis (below)

6, scraper

The quality evaluation indicators of the scraper mainly include hardness, thickness, elasticity, and straightness of the knife edge. Generally use 0.25mm thick flat steel strip with better elasticity, the edge should be sharp, smooth, straight, can be closely matched with the steel plate surface, scraper knife edge is not sharp or defect, it will cause the scraping ink is not clean and Adhesion to the edge of the picture or the production of ink marks on the blade. The severe plate is scraped into a strip. The blade should be at a certain angle with the plate to prevent the blade from falling into the recess of the plate, causing excessive damage. Graphic, if it is found that the blade and the plate contact is not flat, it must be adjusted to close, the length of the blade should be greater than the width of the pattern text near the steel plate, under the premise of scraping off the plate on the non-graphic part of the ink, the pressure of the blade The smaller is better, the less wear and tear is.

7, other

Whether the bottle cap is defective or not: If the bottle cap has a mold release agent, it should be handled carefully and it can be wiped with a plate cleaner.

8, early warning and countermeasures

1 Control of process conditions

The operation of the machine - should be familiar with the working status of each stage of the main work pieces and the operations that can be selected in turn. After a small pilot test is normal, in principle, only the printing surface, buttons and display lights.

Printing plate installation, scraper adjustment - printing plate fixed in the middle of the ink plate, and then adjust the fixture of the printing product, so that the plastic head is aligned with the center of the printing plate and the printing center is also aligned with the printing product center, you can complete the printing Edition installation.

The adjustment of the plastic head, control the speed - in the printing operation, the plastic head drop and lift, to some extent determines the ink transfer temperature, affecting the graphic form, is a very critical moment. Therefore, under the premise that the rubber head, printing materials, ink flow, etc. are all in place, proper slowing down of speed will help improve the quality of printed products.

Add solvent, control the ink flow - according to the amount of printing ink with a good one-time solvent. The general choice of ink: solvent = 1:2 (winter) - 2.5 (summer), that is too slow or dry fast on the use of slow-release agent, too cold and dry to use quick-drying agent. Each interval of a certain time, according to the amount of ink used in printing materials in advance with a certain amount of good release thin ink.

Wet temperature control - the essence is to try to make the solvent in the ink have a relatively stable evaporation rate, a simple way to control the temperature and humidity is to print in an air-conditioned workshop.

2 Problems and Handling Suggestions

Graphic distortion is caused by the load, hardness, radius of curvature of the surface of the plastic head and the thickness, size, depth and depth of the image, and the relative center position between the transfer marks. Choose more than a few models of plastic head, or use the normal steel plate in the past, remove the source of the fault, and select the correct process.
Ink to the light - mainly formed by improper selection and use of ink, not too thin or thick paste to join.

The edge of the imprinted surface is mushy--check whether the squeegee blade is not sharp or nicked. The ink is too thin, the rubber head is damaged, and the steel plate is worn out. Replace it.

The air bubbles of the graphics and texts—air stains on the surface (rubber heads, substrates, etc.) and the materials used (ink glue heads) are deteriorating or improper, and they will not be produced in advance.


(Author/Peng Minggang)
From China Packaging