Talk about ink occupying an important position in security printing

Many security inks can mark “the original has been changed” or prove that an original is true. Here are some safety ink introductions:

1. Chemical solvent reaction ink

These inks will disappear, fade, and become dirty when in contact with wipes, bleach, water, or other solvents.

The ink that reacts with the solvent is usually printed in a background area or in an area of ​​the document. For example, when this ink is used to print the data area of ​​a check, changes in the check can be easily detected. Depending on the ink type, the ink will disappear, fade, and become dirty when changed. These inks can be used for many documents to prevent damage, one of its main applications is discount cheques.

Chemically sensitive inks are evaluated by the ANSI X9B10 committee. Their ability to prevent changes is strong. 3/10 of this capacity is to prevent erasure, 7/10 is to prevent with bleach

2. Erasable ink

Erasable inks provide a clearly visible indicator that is often used to print background colors. If someone wants to change the check, the ink will be erased. A bright or light-colored solid background is most effective because erasing can be significant and the background is not easily copied by a color copying machine. Erasable inks come in a variety of colors, including fluorescent light. One of its applications is the hotel guest check, which includes the background of the area printed with erasable ink. If the customer tries to change the total by erasing, the colored background will disappear.

3. Fluorescent ink

This type of ink, sometimes invisible to the naked eye, emits light under ultraviolet or infrared light. Due to its convertible and hidden features, the heart cannot be accurately reproduced on a color copying machine, making the ink more useful in certain applications. The more popular. Some parts of the cheque, such as the MICR line, can be made fluorescent, or a whole block of the cheque is characterized by a fluorescent color. For example, the watermark is sometimes printed with fluorescent ink. Many currencies in the world are printed with fluorescent inks, which have a wide color range.

4. Infrared ink

This ink absorbs or reflects infrared light. When a box of black infrared ink is printed on a message, the ink is used to cover the "true" or "original" information. This information can only be read under the infrared light. The information itself can also be printed with infrared ink and can only be displayed under infrared light. Just like using fluorescent inks, the person who verifies the document must have the knowledge of the ink presentation and the appropriate equipment.

5. Penetration ink

Permeation inks are commonly used to print MICR data on cheques. The ink penetrates the bottom layer and displays the printed content on the back of the document. Digital changes and other illegal information can be detected by comparing the front and back sides. In some special cases, invisible fluorescent ink can be added as a cover feature to provide special security.

Penetration ink can be used on a cash register to prevent customers from changing information in order to obtain more money from the rebate, and the ink can also prevent copying of the record slip.

6. Thermal Chrome Ink

This ink is also called thermal ink. When a person touches a document, the ink will change color due to the influence of the human body temperature and change back to the original color when it is no longer touched. The ink is now being used on medical prescriptions to reduce medical fraud. General thermal chromium ink is printed on one side of the table below the patient's name, age, address, and date. The ink will automatically disappear when touched.

There are many kinds of color transformations, from blue to colorless, orange to yellow to red to colorless. The dual thermal chromium ink will discolor it when rubbed, and the friction will make it continue to change to another different color. The colorless to non-ferrous conversion of the thermal chromium ink is mainly used for direct mailing, advertising, promotional materials, packaging, labels, education and learning aids, stationery and other novelties; color to colorless thermal chromium ink is mainly used For security documents, because even a color blind can identify colored to colorless transitions and test documents.

Many suppliers offer friction-stained inks that change color due to friction rather than body temperature. Just like with a carbon-free coating, the ink is packaged and coated and the inspector is required to scrape it with a fingernail or object to discover the information. Unlike thermal chrome inks, this ink does not change back to its original color. It also undergoes chemical changes, and the ink automatically turns blue or partially blue when in contact with chemicals. This ink is used for documents, important cheques, and can be printed publicly or implicitly.

Source: 21st Century Fine Chemicals Network