Choosing the right technology for your printing needs based on specific applications isn’t always a simple task. It is important to consider several factors in order to determine what type of printing solution will best suit your needs and often. Some of these factors include:
How Much And What Type Of Information Do You Need to Print?
If you are printing small amounts of data such as a few lines of text with basic production information such as lot/batch number on expiration date, or if the information you are printing changes infrequently (daily) you might consider using thermal transfer. Thermal transfer is able to print whether the material upon which you are printing is stationary (intermittent motion) or on the move (continuous motion). Both types of thermal transfer printer are contact printing technologies meaning they will exert pressure on the material being printed in order to create the print image. If the text is to be printed onto a material that cannot tolerate or support the pressure, a partially filled pack for example, you might want to consider an inkjet coder or laser coder as these are non-contact technologies which never touch the package itself during printing.
More complex print formats, such as barcodes or graphic images, are best addressed using a ‘programmable’ technology such as thermal transfer or thermal inkjet equipped with specific image creation software for just such printing. But remember, because thermal transfer printers exert downward force on the product or package, it is really best suited for printing only on materials such as films and labels where the print surface is fully supported from behind. Cartons can sometimes be printed/coded using thermal transfer coding systems if the carton surface can withstand the downward force of the printhead. For surfaces that flex when pressed or are slightly irregular in shape (and this can irregularity can be caused by something as small as a carton tuck flap) inkjet coders and printers can print on just about any surface as they never touch the material.
An off-line coding system may be best suited to situations where the information or code is printed on a a carton, sleeve, pouch or bag. Such off-line systems also have the added advantage of being able to supply already coded packaging materials to feed several lines at once depending on the application.
The type of information generally falls into one of several categories.
- Simple User Input
- Simple Auto Input
- Complex Data Sets
Simple user input information generally includes lot codes, manufacturing dates, & expiry dates. With digitally programmed technologies such as thermal transfer coders or inkjets, the information can easily be changed on the line by an operator/supervisor by simply keying in the new information on the system controller. In the case of hot foil stamping systems this will mean changing the engraved type characters.
A date, time, or sequential number is referred to as Simple auto input. Little operator input is needed in order to “instruct” the printer as the changing/updating information fields are embedded in the message format. You can’t use such capability with hot foil stamping systems as they only can print static information but both thermal transfer and thermal inkjet are appropriate for automatic message updating.
Both thermal transfer and thermal inkjet are suitable for printing barcodes as they are capable of printing high resolution images (at least 300 dots per inch). Fixed codes or variable information codes can be input to the coder/printer either at the system controller keyboard or via a scanner or other digital input device.
Complex types of information might include a product description, list of ingredients, diagrams, logos or usage instructions. Usually specific software and a computer are used to design, modify and preview these more complex formats . With such more complex, and often larger print images, a user MUST insure that the printer selected has the capability to print the necessary larger area.
What Type of Application Is Required – Intermittent or Continuous Printing?
- Intermittent packaging is where the packaging machine advances and stops the packaging materials as it packs. This type of packaging system is best suited for use with a similarly intermittent motion coder or printer such as a hot stamper or thermal transfer coder as these are able to print on stationary materials.
- Continuous motion packaging machines, where the machine runs without the material stopping, requires a continuous motion printer/coder. At lower speeds, the choice of technology is dictated by the amount of information to be printed. With large amounts of information on flexible material, a large-area-format thermal transfer printer would fit best. Thermal inkjet is another option ideally suited for printing most materials online with the ability to reach higher material speeds of almost 230m/min but can only print smaller areas.
The environment in which a unit is to operate can affect which technology you choose. You need to know, for example, whether the equipment will be subjected to:
- Extreme temperatures (below 5°C or above 35°C)
- Condensation or wash down conditions
- Excessive vibration
Online or offline printing
- Online printing or coding has the advantage of the user knowing that what is going down that production line is packed in material that has been printed on that same packaging line as a fully integrated part of the packaging process.
- Offline printing has the advantage that one offline printing station is usually able to supply several production lines with properly coded packaging materials. It also allows for the late stage customization of packaging materials with information that may be too large or complicated in nature to be added by a smaller print format coder online.
For help in evaluating what sort of printing or coding technology is best suited to your specific need contact a professional at Griffin Rutgers.