Two kinds of UV printing commonly used lamps and general lamp maintenance

The principle is to inject iodine or bromine and other halogen gases into the bulb. At high temperatures, the evaporated tungsten filaments chemically react with halogens, and the sublimated tungsten will resolidify on the tungsten filaments to form a balanced cycle that prevents the tungsten filament from breaking prematurely. Therefore halogen bulbs live longer than incandescent lamps. In addition, halogen bulbs can also operate at higher temperatures than incandescent lamps. Their brightness and efficiency are also higher. However, ordinary glass may soften at this temperature. Therefore halogen bulbs require quartz glass with a higher melting point. Since quartz glass cannot block ultraviolet light, halogen bulbs usually require an additional ultraviolet filter.

Philips (PHILIPS) UV blue and black light source

The phosphor of this tube can convert the arc energy into long-wave ultraviolet radiation of UV-A*. The lamp tube is made of blue-black glass, and there is little visible light that can be transmitted, but it does not affect the luminescent effect.

Uses: Lighting for entertainment venues and advertising. It is mainly used in industrial inspection, textile and chemical industry detection and analysis, banknote inspection, mineralogy, criminology, food production, capture of insects, can be used for a variety of jewels and other falsified paper cutting instruments, etc. It can also be used on stage, nightclubs, etc. Theater and signal lighting.

Maintenance Techniques for UV Light Sources and Accessories in UV Printing

The use of UV inks or UV varnish can result in swelling of the printing roller blanket or finger plate. Severe swelling can cause peeling or surface chipping. It is very important to use a designated eraser and a fingertip.

Many UV ink suppliers will recommend a range of applications, such as the color nitriding of rubber blankets or the nitriding treatment of nitriding can be combined with oil-based UV inks and coatings; while natural rubber and polyethane materials are swollen and not suitable for UV inks. And Varnish; EPDM rubber is particularly suitable for UV inks and coating oils, but not for general inks. The ink roller of the printing press is also based on this principle. It is not always possible to use UV inks and general oil inks. If necessary, the ink must be cleaned to remove any residual chemicals.

General installation of UV lamps should consider the type of printing press. BASF's UV inks and coatings use industrial pressure mercury lamps or microwave H bulbs. If the first one is monochrome, use two 120-W/cm medium-pressure mercury bulbs. Generally, the difficulty of drying four-color UV inks is magenta, yellow and black. Therefore, the sequence of UV color printing should be black, cyan, yellow, magenta.

Some colors are very difficult to deploy. For example, green is made of yellow and cyan tones. In addition, the preparation of opaque colors is also difficult because it reflects off all UV light. The same problem exists for metallic, gold, and silver.

The lifespan of UV mercury lamps is certain, too old lamps can't dry UV ink or varnish. Most instructions on UV lamps indicate that after about 1000 hours of use, UV lamps must be replaced. In actual production, if you feel that you can't dry prints at normal printing speed, you must consider replacing the UV light.

If no reflector is installed, about 80% of the UV light will not be applied to the printed material due to diffusion. Therefore, the UV lamp must be installed with a lamp shade to reflect and focus on the direction of the printed material. Colleagues must also clean and maintain the reflector at all times. If some paper dust or powder dust adheres to the reflector, it will affect the UV lamp reflection effect; if the UV lamp is not used for a long time, the UV lamp cover should be closed to prevent dust from entering.