Precautions for the use of the hottest hidden ink

Precautions for the use of invisible ink

invisible ink is also known as colorless fluorescent ink. It, together with temperature change ink (or thermal ink), eye color change ink, penetration ink, metal color change ink, anti erasure ink, etc., constitute the current domestic anti-counterfeiting ink. Among them, invisible ink is accepted by many factories because of its mature technology, stable quality, complete varieties and various printing methods. Under ordinary light source, colorless fluorescent ink is colorless, transparent or close to white. Printed on paper or plastic film without color. Under ultraviolet light, different varieties will show different colors, including red, yellow, green, blue, white, orange, purple and so on. The above contradictions of our company have exposed two bottlenecks in the polyurethane industry. We have produced colorless fluorescent series inks suitable for various materials (such as paper, various plastic films, metal, glass, rubber, etc.). Types include glue, embossing, silk, gravure printing, etc. But for the same ink, due to its different printing production, anti-counterfeiting pattern design, paper selection and so on, the imprinting and fluorescence effect of the ink will be very different. Shanghai longchen company has been engaged in research and production of anti-counterfeiting inks for many years. In the next stage, some experience of this party's work is summarized as follows:

first, before using colorless fluorescent ink, the ink roller, ink tank, printing plate and other related parts must be thoroughly cleaned to avoid mixing with other colors. Conditional printing plants had better set aside special equipment and replace with new ink rollers

II. Color matching of colorless fluorescent ink and ordinary colored ink. Colorless red printing ink; The fluorescence effect is the best. Colorless red printing blue ink or colorless blue printing red ink has poor fluorescent effect. The depth of the background color has a great impact on the fluorescence brightness. The darker the ink background color is, the worse the fluorescence effect is

III. when printing on paper, colorless fluorescent ink generally makes the final color printing, otherwise it will be covered by other inks, affecting the luminous effect. When printing transparent plastic, the situation is different. When printing, fluorescent ink is used as the final color; When printing inside, make the first color

IV. colorless fluorescent ink is not absolutely colorless or has absolutely no imprint. On white paper, even if a completely transparent and colorless varnish is printed, there will be visual differences due to the different refraction and reflection coefficients between paper and varnish, resulting in the difference between oil stains and the brightness of the paper surface

v. colorless fluorescent ink is the soul of all components. Only under the following specific conditions can imprinting (or basic invisibility) be reduced:

1. Change the color block of the pattern or text into lines

2. Fluorescent ink is best printed on the part with background color, which is conducive to covering the fluorescent ink

3. Paper with good absorption should be selected. The ink absorption performance of invoice paper is better than that of copper paper and paperboard

VI. factors affecting fluorescence brightness:

1. Paper factors. Securities paper or paper without fluorescent brightener should be selected, so that the effect of fluorescence is ideal. When printing on paper (plain paper) with fluorescent brightener, the fluorescent effect will be significantly weakened. The more the brightener content of the paper, the weaker the fluorescence effect; Otherwise, it is stronger. Therefore, when using plain paper, try to choose paper with low brightener

2. Ink layer thickness. The thinner the printing ink layer, the weaker the fluorescence effect; The thicker the ink layer, the stronger the fluorescence effect, but at the same time, the more obvious the imprinting

if users pay attention to these characteristics when using colorless fluorescent ink, they will certainly achieve good printing and counterfeiting effects e-mail:amyxiang@ jenniferfang@

reprinted from: ink information