Several points to pay attention to when using UV varnish
We are a big printing company in Shenzhen China . We offer all book publications, hardcover book printing, papercover book printing, hardcover notebook, sprial book printing, saddle stiching book printing, booklet printing,packaging box, calendars, all kinds of PVC, product brochures, notes, Children's book, stickers, all kinds of special paper color printing products, game cardand so on.
For more information please visit
http://www.joyful-printing.com. ENG only
http://www.joyful-printing.net
http://www.joyful-printing.org
email: info@joyful-printing.net
First, UV varnish is divided into two different formulas: winter type and summer type.
1. When using, pay attention to distinguish between season and weather temperature changes, and choose the applicable varnish. The winter formula has a lower solids content than the summer formula, in order to improve the smoothing performance of the varnish in the winter when the temperature is lower; in the summer, the temperature is higher, and the solid content is increased to increase the curing speed of the UV.
2. If the winter formula is used in the summer, it will cause the UV oil to cure incompletely, which is easy to cause anti-sticking; otherwise, the summer formula will be used in the winter, which will cause poor UV oil smoothing performance, resulting in foaming and orange peel.
Second, the UV varnish should be fully stirred before use.
UV varnish is made up of many kinds of chemical raw materials. After not being placed for a long time, some chemical raw materials in the barrel will be separated, and should be fully stirred before use.
Third, to avoid not completely dry and anti-stick method
1. The speed of the light curing machine is adjusted to the slowest speed that does not affect production.
2. Choose 2 * 5.6kw light curing machine, the normal speed is 30m / min.
3. UV lamps that are not full of service life (national standard: 800h~1000h, domestic lamps about 500h).
4. UV lamp and lampshade should be cleaned once a month with alcohol to avoid the effect of dust blocking.
5. After the product has passed the UV curing machine, it cannot be stacked immediately. It should be divided into 5-10 sheets and placed on the drying rack for 15 minutes to be stacked.
6. If you encounter dark blue, black, special substrates, use quick-drying UV varnish or reduce the speed.
Fourth, how to detect whether UV matt film varnish is completely dry and avoid anti-stick phenomenon
UV matt film varnish is made from a resin with a low melting point. On a hot summer day, if it is not completely dry, it is easy to stick. First of all, the drying procedure of UV varnish is divided into dry and deep dry, so it is impossible to rely on the hand mold alone. At present, there is no definite method for testing and drying in the industry, but the following three methods can be provided according to experience:
1. Use a dry index finger to press the surface of the dried UV varnish for 5 seconds to release the non-sticky hand for complete drying.
2. Several pieces of finished product are stacked with a force of 50 kg to 100 kg for 2-3 hours.
3. Wipe the surface with talc.