Several Screen Printing Processes For High-end Packaging Boxes (below)

Several screen printing processes for high-end packaging boxes (below)

1. Refraction original design

The main points of the design of the refraction manuscript are as follows: draw the part of the image that needs to be refracted into a millimeter bisector, divide each millimeter of length into 5 to 8 bisectors, and each bisector is divided into black and white 10 to 16, etc. Points, taking 16 as an example, can be designed as black 4 white 12, or black 8 white 8. The lines are divided into three types: straight lines, circular arcs, and ellipses, and the lines and arcs kiss each other as the image changes.

The appearance of the refraction pattern is fine and complex, and its internal structure cannot be seen with the naked eye. Under a microscope with a magnification of more than 40 times, it can be seen at a glance that the refractogram is composed of several or dozens of lines arranged at equal distances but with different angles and radians. The thickness of the refraction lines should be 0.10-0.15μm, which can be produced by a high-resolution laser imagesetter.

2. Requirements for printing materials

Screen printing ice-pattern coated paper is a layer of high-gloss vacuum aluminized film covered on the surface of high-smooth cardboard. The quality of the coating is one of the key factors determining the quality of ice-pattern screen printing. The surface gloss of the film has a great influence on the quality of the product. The higher the surface gloss, the stronger the reflection, the better the ice effect, and the brighter and brighter the pattern. Since the printed product needs to be UV cured immediately, this requires the film to have certain light resistance and heat resistance, that is, during the entire curing process, it is required that the film should not be bubbling, and it should not be separated from the underlying cardboard.

3. Ice flower ink

Binghua ink is a special UV ink, and its printing patterns can be divided into three types: large, medium and small. The large pattern is about 6-8mm, the medium pattern is about 4-6mm, and the small pattern is about 2-4mm. If these three patterns of ice flower inks are mixed and used, a new surface finishing effect of large flowers and small flowers can be created.

Binghua ink is transparent, not only does not cover the underlying ink, but also plays a certain role in rendering the color of the underlying ink, so that the printed pattern presents a colorful visual effect.

4. Ice flower screen printing

The hardness of the printing squeegee is HS65-75, and the squeegee and printing effect are better. In printing, the ice ink adopts the intermittent curing method, and the conveying speed of the printed product on the conveyor belt of the curing machine is 25-35 m/min. The curing light source is 6 UV lamps arranged in parallel, and the power intensity is 60-80W/cm. During curing, after the printed product passes through the first 3 UV lamps, it should be blown with wind in the cooling area, then enter the curing area of the last 3 lamps, and then blown with cold air, so that the curing effect is better.

Refractive screen printing process

The refraction screen printing technology emerging in recent years is a new star in the packaging screen printing family. The traditional refraction effect is generally to first make a copper-zinc plate with refraction texture, and use a circular or circular flat letterpress printing machine to press lines of different angles on gold and silver cardboard to produce a refraction texture effect. The disadvantage of this method is that the cost of plate making is high and the effect is not ideal. Screen printing can easily print ultra-fine concave-convex lines on mirror gold and silver cardboard, which will produce colorful refraction effects after being irradiated by light, making the screen-printed packaging box more noble and gorgeous.

The process of refraction screen printing process is: refraction original design → stretch screen → cleaning and roughening screen plate → coating photosensitive glue → exposure → developing → plate revision → secondary exposure → printing.