vesileimaus

Vesileimaus, a Finnish term, translates to "watermark" in English. It refers to a design or pattern that is embedded into paper during the manufacturing process. This is achieved by varying the thickness of the paper pulp, creating areas that are more or less translucent when held up to light. Historically, watermarks were used by papermakers as a form of branding and quality control, allowing them to identify their products.

The technique of creating watermarks dates back to the late 13th century in Italy. Over time, their use expanded beyond simple identification. In the realm of currency and important documents, watermarks serve as a security feature to deter counterfeiting. Their intricate designs and the specialized manufacturing process make them difficult to replicate accurately.

In modern times, vesileimaus is still a common feature in banknotes, passports, official certificates, and high-quality stationery. The complexity of a watermark can range from a simple shape or initial to a detailed image. The method of production dictates the type of watermark. A "true watermark" is created during the papermaking process by impressing a wire design onto the wet pulp. A "surface watermark" is applied later to the dry paper, but these are generally less secure and easier to imitate. The presence and quality of a vesileimaus are often indicators of the authenticity and value of a paper product.