We all love the beautiful intricate gold design on an invitation card or the gold embossed writing on a chocolate wrapper, but how many of us stop to find out about the intricate science and technology that goes into developing these commodities. Science has come of age and with it many technologies, one such being ‘lithography’ or the ‘art of printing’. We often do not realise the wonders of lithography that touches our lives every day. Dating back to the 19th century, hot stamping was a popular technique of embossing especially in books but later found its way into gold personalisation and monogramming on various surfaces most frequently on leather and paper. A traditional hot foil printing machine or hot stamping machine uses either hot foil dies (a metallic printing plate) or traditional movable loose letters for printing purposes. A typical printing job with hot foil dies involves placing a die or line of type on the heated print head of the stamping machine; the product to be stamped is placed underneath with a metalized or pigment foil in between the two. The heated die presses down hard on the foil and a combined force of pressure and time leads to the product being embossed with an exact impression of the die with the pigment or metalized foil.
Types Of Hot Foil Dies:-
Hot foil dies are metal, polymer or silicone printing blocks with photo-etched or machine carved logos, text or graphic images. They are the backbone of hot stamping technology and are the only means of machine embossing on merchandise and goods using hot stamping. The material, cost, and durability of the hot foil dies may vary according to purpose and expenditure. Hot foil dies are of the following types:
- Magnesium Dies: Inexpensive and durable, these dies are chemical or photo etched giving excellent and clean end results on hot stamping.
- Brass Dies: Having superior heat conductivity, they are hand or computerised machine engraved with better image quality and precision. They are also more durable and thus more expensive. They require a longer production time as compared to magnesium dies.
- Silicone Dies: Made from soft density silicone they are low heat conductive dies that can fit into curved or irregular surfaces. Conventionally used for plastic and acrylic printing they are the only means of printing on an irregular surface. They are the most expensive and help in dimensional conformity.
- Polymer Dies: They can be made ‘in-house’ and are the newest additions to die making. All you need is a UV exposure unit, inkjet printer, and blank polymer sheets. They are one time use photosensitive, steel backed, water soluble resin blocks that are almost inexpensive and can be self made within an hour at home.
- Combination Dies: As the name suggests it uses a combination of two dies that are usually machine etched from the best quality metal and fibreglass. It provides a raised or embossed effect on paper or card. It gives high quality finesse and effect to the end product.
Hot Foil Dies are the base of hot foil stamping without which engraving or embossing would be impossible. So if you are thinking about printing or hot foil stamping you must choose your hot foil dies with great precision and care.