Luminescence

IN Arora group brings in India Luminescence, the world leader in security inks, which offers a with security features. The products can be printed using various printing techniques including litho, dry offset, letterpress, flexo, gravure and screen applications.

  1. Thermochromic Inks: These are heat sensitive ink that disappear, or change colour, when exposed to temperatures above their set level. They are reversible in nature.In addition to our range of Reversible Thermochromic inks we have also developed a number of Irreversible Thermochromic inks.

  2. Optically Variable Inks: LUMINESCENCE produce a range of five standard Optically Variable inks. They change instantly from one colour to another depending on the angle at which the ink is viewed on the document. It must be printed on black or a dark colour to see the effect.

  3. Fluorescent Inks: These inks fluoresce brightly when excited by 365nm UV light. Inks available include:

    • Invisible inks can be manufactured to emit red, blue, green, turquoise, aquamarine, gold or yellow fluorescence under long wave ultraviolet light.
    • Fluorescent effects can be added to many other security inks; such as Numbering (MICR), Thermochromic and Erasable inks.
    • Machine reading of such inks is possible.

  4. Photochromic Inks:Photochromic inks change colour when they are illuminated with either ultra violet light or natural daylight. They are colourless in their natural state and when exposed they produce their visible colour. These inks are reversible; reverting to their colourless state when the light source is removed. The change in colour is more immediate and spectacular in direct sunlight than under 365nm UV lamps.

  5. Metameric Inks: Metameric features consist of two similarly coloured inks that are almost indistinguishable in normal light conditions. However, when a filter (a coloured piece of plastic) is placed over the print, one ink disappears while the other appears darker. This allows for hidden words or images to become apparent and thus identify the document as genuine.

  6. Coin Reactive Inks:Coin Reactive inks are white base inks designed to appear 'invisible on white papers. When a coin is rubbed on the printed area a grey/black colour becomes immediately and clearly apparent.

  7. InfraRed Fluorescent Inks: InfraRed fluorescence is similar in effect to UV fluorescence. The ink is excited by an InfraRed light source (around 800-900nm) to emit fluorescence in the visible spectrum.

  8. InfraRed Invisible/ Visible Inks: LUMINESCENCE produce a range of visible inks that are invisible (transparent) in the InfraRed. These are generally used alongside an InfraRed visible ink. When viewed under a suitable scanner the IR Invisible component disappears; thus verifying the document. The scanner must read at 790nm or higher.

  9. UV and IR Absorbing Inks: These inks absorb in UV or IR and can be used for a variety of practical and security applications.

  10. UV Absorbing inks: These inks absorb UV light and can be used on UV bright paper to create an inverse fluorescent design or a barcode/datamatrix code that can be read by a scanner fitted with a UV reading optic. This creates a secure, invisible barcode that can be used for secure track and trace systems.

  11. IR Absorbing inks: These inks are invisible and absorb infrared light (790nm and higher). It can be used on almost any paper or plastic and will not respond to other light sources. Only scanners using specially fitted IR technology can read this code, which makes it more secure than the more commonly used UV option.

  12. Affirm: Affirm is a new machine-readable security feature from LUMINESCENCE. Consisting of special printed ink and a small hand-held reader, the system is highly adaptable and can be used to protect almost any value document or product against fraud.Affirm material can be printed as an invisible ink or added to existing colours. When the reader is held against the printed area, and the verify button is pushed, a green LED is activated and a high-pitched beep' is produced. This confirms that the Affirm material is present and the document/product is genuine.

  13. Reactor Pen Inks: A range of Pen Reactive Ink systems has been developed by LUMINESCENCE for verification of items on site.These systems work by printing onto the document either a solid block of colourless ink, or a suitable invisible printed slogan, when this printed area is marked with the special pen an intense colour is produced. The invisible base inks can react to become black, blue, green, red or orange.

  14. Fire & Ice: Highly secure ink that is invisible in normal lighting and fluoresces blue in long-wave UV light. However, if the UV light source is moved across the printed area and red flash is produced. Because of this combination of a cool blue fluorescence and bright red flash the ink has been named 'Fire & Ice'.

  15. Bi-Fluorescent Inks: These are invisible inks that fluoresce one colour when excited by long wave 365nm UV light and another shade when subjected to short wave 254nm UV light. It is also possible to make Bi-Fluorescent combinations using 313nm and infrared responses.


  1. Tri-Fluorescent:These are invisible inks that fluoresce three different colours in different frequency light.

  2. QFX: QFX is a new security feature from LUMINESCENCE that produces four different fluorescent colours from one printed ink, The ink is invisible in normal light, but fluoresces:

    • Yellow/Green in 254nm short-wave UV light
    • Red in 313nm mid-wave UV light
    • Blue in 365nm long-wave UV light
    • Green in 980nm infrared light

  3. Solvent Sensitive (Lumisol) Inks:Usually printed as a background pattern to protect value documents, Solvent Sensitive inks are formulated to show strong reactions to organic solvents. Alteration of documents is possible through total immersion in, or by more subtle localised use of, solvents and alcohols.

  4. Aquafuge Inks: These are water-based inks that offer a degree of security against falsification or unauthorised amendment of documents. Traditionally this type of ink is used to prevent any alteration by water-based reagents on the most sensitive areas of a document (the sections with the payee, written amount and cashbox

  5. Secondary Fluorescent Inks: Secondary Fluorescent inks have been formulated to show no fluorescence under 365nm ultraviolet light when initially printed. However, if the document is treated with water, or an aqueous ink eradicator, a pronounced fluorescence is observed when viewed under 365nm ultraviolet.

  6. Combifuge Inks: By combining the following properties:

    • Aqua Fugitivity (water fugitivity)
    • Secondary Fluorescence
    • Solvent Sensitivity
    It is possible to produce an ink that meets all of APACS current standards (except Primary Fluorescence) in a one unit application.

  7. Aquaset Inks: As a complementary product to our range of aquafuge/solvent sensitive inks, LUMINESCENCE also produce Aquaset inks. These were developed to offer a good reaction to solvent attack (showing pronounced 'bleed') and also to 'disappear' when documents are attacked with water based chemical reactions of the oxidation-reduction type.

    8. The main difference between this type of ink and our standard range of Aquafuge/solvent sensitive inks is that Aquaset inks hard dry to be impervious to water attack within 24 hours.

  8. Bleach Reactive Inks: These inks are usually printed on the background of a document either as a solid or as text. They have been formulated to be invisible until contacted with bleaching chemicals (chlorine, sodium hypochlorite, etc) when it will produce a strong brown colour. This shows that the document has been in contact with bleach and will be obvious to the examiner. If the ink has been printed as text then the wording, for example "VOID" will become immediately apparent. This ink can be overprinted with other inks and is also laser compatible. This ink can be used to replace the bleach reactive component often included in security papers.

  9. Erasable Inks: Erasable inks are usually printed as an overall background screen on a document. They have been formulated in such a way that the print will be removed when subjected to mechanical abrasion; e.g. by an eraser, scraper or scalpel.

  10. Irreversible Thermochromic Inks: In addition to our range of Reversible Thermochromic inks we have also developed a number of Irreversible Thermochromic inks. These inks are invisible until exposed to high temperatures, when an intense colour develops.

  11. Magnetic (M.I.C.R.) Inks:Luminescence MICRO inks are suitable for most magnetic character recognition applications. They are especially formulated for E13B type magnetic character encoding on cheques.

  12. Papermark Ink: As the name suggests, this ink is used to simulate a watermark effect on documents. This result is achieved by the ink penetrating into the substrate, causing the refractive index to change, and therefore become more translucent than the unprinted area.

  13. Phosphorescent Inks:These are long persistence luminescent/phosphorescent inks with glow in the dark properties from an ability to absorb high-energy radiation (i.e., uv light), and emit visible light of a longer wavelength. They also possessphosphorescent characteristics that allow them to emit visible light for a long period after excitation