Embossing
Characters can be embossed on cards to show names and numbers. This is accomplished using a hammer and anvil design for each character which is punched one at a time into the face of a card. Embossing is described in detail in ISO / IEC 7811 (www.iso.org). which identifies how to properly emboss characters on a card. The original specifications were designed for financial cards (credit, debit, ATM). Subsequently, cards have been used by all sorts of organizations seeking to use cards. There are no official standards for these additional uses. The most common changes beyond the original intent of the standard are:

• Embossing above the four lines called for in the specification: Requires a sturdy card to support additional lines due to warping caused by the embossers
• Adding thermal printing to the card in addition to the embossing.
• Having fewer or more than the standard four lines on a card.
• Not using the standard type faces in the standard locations.
• Embossing on substrates not identified by the ISO standards: 15mil -28mil plastic or 18mil-24mil paper cards.

In general, 19 digits of the OCR-A font (numbers only) can be embossed on the account number line, and 29 alpha/numeric characters of the Farrington 7b font can be printed on the other lines.

Embossing is the slowest form of personalization. It is the preferred method for secure cards (Visa, MC, AMEX), and all forms of advertising products. The feel of an embossed card through the envelope is most likely to generate interest from the consumer and cause them to open the direct mail piece. This is reported to provide significant lift to these packages more than justifying the additional cost.

Thermal Printing
Became popular on plastic cards in the late 1980s. The idea was to create tamperproof printing on a plastic surface. It requires a thermal, non-impact, non-embedding printing head containing dot printing elements which are individually and selectively heated and non-heated for the purpose of releasing ink from a foil interposed between the thermal print head and the surface of the card. Over the year many different colors of ribbon have been developed for different uses and looks. Thermal ribbons were also created to apply scratch-off to a card specifically for the purpose of covering a PIN number. Typically thermal printing can occur anywhere on the plastic surface up to 1/8” from the edge of the card.

Duplex or 2-sided thermal printing can be accomplished in two different ways. Some machines have flipping mechanisms which turn the card over and feed it back through the print head assembly. These machines can only print in one color of foil on both sides of the card. Others have multiple print heads that are dedicated to front or back printing which can be individually loaded with a specific foil color allowing for many different foils to be used on one card. In general, multiple print heads cannot be used to “hair register” colors. The manufacturers generally specify + or - 1/10” is the limit of their printing accuracy.

Newer printing designs allow for full color printing of cards. This is accomplished in two different ways. First, is direct-to-substrate thermal printing using 4-color ribbons. The ribbon has 4 colors pre-printed them in sequence. The ribbon is advanced color by color while the card is stationary, imaging in the thermal print process described above. This process leaves a small white line around the edges of the card and is a limitation of the direct thermal process. Alternatively, retransfer printing allows for a thermal process against a substrate which then has that image transferred to plastic card. In this process the image fully covers the card and creates a better image. Color ribbon printing of any kind by its nature is a more expensive process than litho printing except in the smallest quantities.

Inkjet Printing
Inkjet printing has evolved dramatically in the last 10 years for plastic cards. Originally, magnetic stripe encoding equipment was mated up with MEK (methyl ethyl ketone) or solvent-based inkjet printers to provide the first high speed print devices for card production. Disadvantages include the dangerous vapors released and special drying equipment.

In the last 10 years the industry has largely migrated to drop-on-demand (DOD) printing for card products. The inks consist primarily of acrylic monomers with an initiator package and dries easily by exposing it to strong UV-light. They are dry as soon as they pass under the UV light and can be applied to a wide range of substrates unlike thermal printing which is almost exclusively limited to the higher cost PVC laminated card product. However, the ink is relatively expensive which is one disadvantage of using DOD with heavy ink application projects.

One thing to look out for is whether or not DOD ink will adhere properly to the surface of the card or material being inkjet printed. A thorough test should always be done before large scale production begins to insure materials and finishing capability.

Encoding
Cards often contain a magnetic stripe for the purpose of being swipe read in a magnetic (mag) stripe reader to acquire the cardholder data accurately and quickly. The standards for mag stripe encoding were established in ISO/IEC 7810, ISO/IEC 7811, ISO/IEC 7812, ISO/IEC 7813, ISO 8583, and ISO 4909, define the physical properties of the card, including size, flexibility, location of the magstripe, magnetic characteristics, and data formats. They also provide the standards for financial cards.

The mag stripe card was developed by IBM in the 1960’s. Since the first magstripes were invented they now come in many different types and sizes. There are two main varieties: high-coercivity (HiCo) at 2750 or 4000 Oe and low-coercivity (LoCo) at 300 or 600 Oe. High-coercivity magstripes are harder to erase, and therefore are appropriate for cards that are frequently used or that need to have a long life. Low-coercivity mag stripes require a lower amount of magnetic energy to record, and hence the card writers are much cheaper than machines which are capable of recording high-coercivity magstripes. A card reader can read either type of mag stripe, and a high-coercivity card writer may write both high and low-coercivity cards (most have two settings, but writing a LoCo card in HiCo may sometimes work), while a low-coercivity card writer may write only low-coercivity cards.
 
In practical terms, usually low coercivity magnetic stripes are a light brown color, and high coercivity stripes are nearly black. There are exceptions of course including newer proprietary mag stripe color formulations. High coercivity stripes are resistant to damage from most magnets likely to be owned by consumers. Low coercivity stripes are easily damaged by even a brief contact with a magnetic purse strap or fastener.

Magnetic stripe cards are used in very high volumes in the mass transit sector, replacing paper based tickets with either a directly applied magnetic slurry or hot foil stripe. Slurry applied stripes are generally less expensive to produce and are less resilient but are suitable for cards meant to be disposed after a few uses.