Security features in paper structure.

To further protect against counterfeiting, various security features are applied directly into the structure of the paper during the manufacturing. The most common security features include watermarks, security fibers, or the use of chemical protection.

Overview of security features in the structure of the paper:


Watermark (watermark, filigree) is drawing in the paper structure (logos, texts, motives), which is formed by controlled changes in the paper machine and visible against the light. The original purpose of the watermarking was to identify the origin of the watermark paper, and paper mill where the paper material was manufactured. Today, it is considered as one of the protective and security features. The SPM watermark feature is done in the wet section of a paper machine, using the dandy roll.

The pulp (slurry of paper fibers and other pulp/paper products) flows onto the paper-machine wire and using the egutter (dandy roll) a final emboss is compressed. Depending on the shape of emboss, the paper sheet thickness and density can vary.

Each dandy roll is manufactured right on site at SPM, providing a maximum security and additional protection against a damage, while minimizing a lead time for each unit to be manufactured.

Customers can request a custom, unique watermark pattern, thus becoming its sole owner. If a customer does not require a custom, proprietary patter, SPM can provide a generic pattern available from the list of watermark themes already designed by SPM.

Universal watermarks:

Papers with a watermark are produced to a weight of 60 - 250 g/m2. Papers with a watermark are used for business contracts and other important documents, which are secured against counterfeiting. They may be used for prestige presentations for serious clients, companies, agencies and state institutions.

UMBRELLAS 70 - 120 g/m²

UMBRELLAS 70 - 120 g/m²

ELLIPSE 70 - 130 g/m²

ELLIPSE 70 - 130 g/m²

ESSES 60 - 200 g/m²

ESSES 60 - 200 g/m²

FLOWERS 70 - 130 g/m²

FLOWERS 70 - 130 g/m²

LION SHIELD 80 - 130 g/m²

LION SHIELD 80 - 130 g/m²

PYRAMID 60 - 150 g/m²

PYRAMID 60 - 150 g/m²

TRIANGLES 75 - 120 g/m²

TRIANGLES 75 - 120 g/m²

WAVY LINES 80 - 120 g/m²

WAVY LINES 80 - 120 g/m²

YPSYLON 70 - 130 g/m²

YPSYLON 70 - 130 g/m²

Watermark placement:

  • Continuous watermark

  • Watermark design is placed continuously over the entire surface of the sheet of paper, similar to a patterns on a wall paper. This type of watermark is used mainly for stock certificates, legal documents, travel tickets, tax stamps, vouchers, etc.

  • Registered watermark in a specified location

  • The watermark motif is placed at a particular location according to the customer´s specification, ensuring the identical appearance of all documents.
    This type of watermark is used for company documents, passports, diplomas, certificates, etc.

    Types of watermarks:

  • Light watermark

  • The motif on the paper is lighter than the rest of the surface, in a given place the density of the paper is lighter.

  • Dark watermark

  • The motif on the paper is darker than the rest of the surface. In this place the density of the paper is denser (heavier)

  • Combined, or if the multi-tone watermark

  • It is the ultimate level of protection formed in the paper. Watermark patters and shapes, when viewed against the light, are created with both, light and dark element.

    Watermark visible under UV light

    Standard watermarks feature can be enhanced with additional security, allowing the watermark to be also visible under UV light. A high level of security is determined by the visibility on one side of the watermark under UV light, while on the other side the watermark is completely unreadable.
    This enables the paper to be printed with UV inks on one side.
    It offers very effective protection, which cannot be achieved using other methods, especially in combination with colour pigments. Falsified watermark does not appear under UV light.

    Electrotype watermark

    Electrotype watermarks are used to enhance features of a standard watermark. It is always used in a combination with a standard watermarks. There are clearly certain functions of watermark that expand the tonal range and provide high contrast watermark area that are easily noticeable against the light. Numbers and letters are typically displayed as highlighted elements within the structure of the watermark. This type of watermarking is another way of protection against counterfeiting, and it would be almost impossible to work around (or simulate) this level of embedded protection. As with a typical watermark method, this type is also created during the wet process.

    Security fibres

    Security fibres are added to the structure of the paper during its manufacture and may be visible in daylight, visible only under UV light, or a combination of both. Part of them may be invisible in normal light, however, when using ultraviolet light they appear brightly. Some fibers may have characteristics that are normally visible, never the less, under UV light entirely changes colors. Security threads can have different colors, length and thickness and in different concentrations, and can be used as multicolored fibers. With all mentioned fibers SPM guarantees precise dimensions and characteristics, i. e. the color shade or fiber luminance.
    Each customer may choose the most suitable option for a specific type of paper.

    Chemical protection

    To protect against data modification either printed or written on a protected document we add a substance to the structure of the paper. In any attempt to chemically erase the data, a chemical reaction on paper causes a stain, impossible to remove. This type of protection is not evident at first sight. It starts to act as soon as a chemical agent is applied to a sheet of paper protected in this way. Elements spread over the sheet of paper are sensitive to chemical agents.
    This effect occurs by changing the pH of the paper, which is caused by the use of various agents that are added to paper during the manufacture. Such secured paper is protected against different types of chemicals.

    For each chemical (to be protected from) a different kind of agent is added to the paper:

  • Protection against acid
  • Protection against alkaline
  • Protection against organic solvents
  • Protection against bleaching agents

  • Papers with chemical security are relatively widespread, and some types follow their international specifications. These are typically given by papers with defined physical properties, such as basis weight, thickness, smoothness, and others. This protection is used against counterfeiting of data either written or printed on a security paper and to verify its legality, e. g. checks, tickets, diplomas, official state documents, etc.

    Instant chemical reaction

    To quickly verify the authenticity of the paper, a substance in the structure of the paper is used, which reacts when a control pen (BLANKA) is used. When using a control pen on regular paper there is no reaction, however, when using a control pen on our security paper, a blue or pink reaction will appear based on the type of pen used.

    IR detection

    LUX LASER® is a brand new and proven security feature, which reacts to light in IR spectrum of 980 nm. When the document is exposed to a laser beam, a visible light is emitted. If it shines - then the document is the ORIGINAL, if it does not shine - the document is likely a FALSIFICATION. The advantage of this protection is that it does not permanently damage the original.
    LUX LASER® can produced in green, red, blue, white and orange colors. Application of the feature can be over the surface area, or in unlimited stripes with a custom density and colour combinations. LUX LASER® is provided with a guarantee of minimum 20 years. It is irremovable, flameproof (even ash can be verified !). LUX LASER® is protected under worldwide patents and industrial applications.


    Planchettes are small particles dispersed to the main paper layer during the manufacturing process. They contain certain attributes which are not changed when they are added to the structure of the paper. Relatively easy to identify with a microscope if the documents is printed on correct, secured paper. Planchet can be made of paper, but also metallic or transparent. They can also fluoresce under UV light, or may be made of iridescent materials changing colors.


    Somewhat specific way securing safety fiber is the use of metal fibers, also known as microwires. Microwires are exclusive magnetically bipolar security fibres made of two metal alloys, ideally covered by elastic flameproof glass with a minimum length of 10 mm and resistant to a damage to individual fibers with a fire or corrosion. They are also visible to the eye on the paper. Microwires may also be used for laboratory verification after the document is burned. Detection may be audible as well as visual.
    Paper with microwires may be identified by all ordinary metal-sensitive detectors as well as special (table or gate) detectors, recognisable on the basis of the change in polarity and "their" microwires. This can confuse, but also to distinguish genuine from counterfeit documents using metal or magnetic inks and other particles.

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