Getting Started in the Solvent-Based Inkjet Printing

By Robert C. Flipse
Image Systems & Supplies Inc.

Glossary of Terms
Solvent-based printer: Very simply, inkjet printing using solvent-based inks, similar to screen printing inks but the inks are formulated for digital printing.

Thermal printing: The technology behind “Bubble Jet” printers uses heat to fire the ink onto the substrate. Attempts at running solvent inks in thermal printers were unsuccessful. Very particular ink chemistry due to physical properties required.

Piezo printing: Fires the ink by using an electronically excited crystal membrane to push the ink through the print orifice. Less demanding ink technologies required due to mechanical firing of the ink droplets.

RIP: Your raster image processor is what turns small pictures and objects into large ones with minimal quality loss.

Color Management: A system consisting of software and instruments to color balance the look of a print when using different inks and/or media.

Vector Objects: Object creating in popular drawing programs such as Adobe Illustrator or Corel Draw! are made of lines and arcs and may be blown up to any size without degradation versus pixels. Use vector objects where possible for text and logo.

Bitmap Files: Pictures or objects in a file that are made up of pixels rather than lines and arcs. Bitmap files are made of pixels, an array of adjoined squares containing the color information. When enlarged, they will reveal jagged edges and give poor print resolution.

Postscript: A universal file standard that allows you to combine vector and bitmap elements in a single job. Popular in the past and still in widespread use today. An example is “doby illustrator”.

PDF: An acronym for Portable Document Format, has become a new universal standard for sharing files across typically Mac and PC platforms. Includes all fonts and bitmaps to make file readable and usable to end party.

Selection of Printer
You must think of all elements as part of a “system.” This includes media, inks, RIP, CMS, LAMS and VAR.

  • Media – work backwards from the needs of the intended application. Ask the right questions: where is it going to go? How long does it need to last? What do you have to mount your graphic on?
  • Inks – solvent inks give good durability but don’t work equally well on all substrates.
  • Color Management System– vital if you are to have sharp, accurate output. Matching pms colors is an expectation in today’s world. There are software programs to assist with this process such as X-rite
  • RIP – must have a good RIP for speed and workflow, integrated with CMS.
  • Lamination – does the job call for additional finishing?
  • VAR – value added reseller-a vital component in making you successful out of the box. Make sure that you are using equipment efficiently.

A Brief History of Inkjet Printing

  • Developed in early days for CAD, or computer aided design applications.
  • First big player was Lasermaster in early ‘90’s, using an Encad printer and a proprietary RIP and color management for good output.
  • They were very slow, with speeds not much more than 10-12 square feet per hour. Today printers rate can be 1000 square feet per hour.
  • Offered only dye-based indoor inks.

Types of Printers

Entry Level

  • $10,000 or less for the printer
  • May print with both dye (food coloring powder) and pigmented inks.
  • Are aqueous, or water-based that require special, coated media.
  • Speeds have increased, but these are not production monsters. Rate is 40-45 square feet per hour)
  • Higher cost per print due to ink and media needs which are often proprietary.
  • Quality is not as big of an issue any more. The concern is ink costs. Many types a cheap printer has higher ink costs and fabric limitations.

Midrange

  • Price range from $15,000 to $40,000 for the printer.
  • May print with both dye (water-based) and pigmented inks.
  • Both aqueous and solvent printers fall into this category.
  • Some in this range are very, very fast—advertising 400 square feet per hour or more.
  • Cost per print varies depending on design of the printer; media used, and ink system.

High End

  • Price range from $50,000 to over $400,000 for the printer
  • Very specific ink technologies. (Examples: L&P, 3M)
  • Designed for very high production at low cost.
  • Speeds can be over 1000 square feet per hour. (Go to fast and quality is less)
  • Very specific high volume opportunities where cost of output justifies cost of equipment.
  • Usually have the lowest ink and media costs “better be able to feed the beast”

Benefits of solvent-based printing

  • Direct print to substrate lowers media costs. Ink is usually cheaper too. Ink and media bonding adds durability to prints. This is the preferred method of printing when the job has a large quantity of printing.
  • Pigmented inks give added UV Life when used outdoors. You must remember with solvent-based inkjet printers you must keep he heads moist. To achieve this you must be using the printer all the time. Water-based inks are used for occasional printing because of this factor.

Ask your self these questions when selecting a printer

  • How big do I want to print? 64 inches or less is most common. Over 100 inches is called grand format printing.
  • How fast do I want to print? It is important to know what kind of jobs you want to do or how fast you need to print.
  • How long has the printer been in the field? If possible, talk to someone who has the printer you are interested in.
  • What will be your end application? You print from lightweight banner material to heavy wallpaper or other thicker substrates. The most versatile will cost more. Head clearance is important and solvent printers are best for this purpose.
  • What is the warranty on the printer? Three to five years is a good guarantee.
  • Solvent ink jet printers require more maintenance and must be kept clean.

Regarding Media and Inks

  • With solvent ink jet printing the media is uncoated, resulting in a purchase savings of 50-75% or more.
  • Gives you more variety of what to choose from
  • Solvent ink chemistry attacks and bonds with substrate. (Solvent melts vinyl, inks evaporate and bonds. Need coating to hold in place.)
  • Aqueous printers need coated substrate to hold the ink in place. Shinier fabrics and a plasticizer to make shiny so ink migrates.
  • Not all uncoated media will print well as ink and substrate chemistry varies.
  • Banner, Flag and Graphics Specifiers Guide – source for fabrics for printing

Quick Ink Primer
ECO Solvent

  • Future is not good
  • This is a light duty solvent, supposedly ventilation required. Drying often an issue.
  • Requires coated materials like aqueous with few available.
  • Media and ink cost higher than aqueous but prints last longer.
  • Printers are often modified aqueous printers and not all have been fully adapted to the task.
  • Some systems out there sold by ink manufacturers with poor warranty coverage.
  • Not HAZMAT for environmental and freight issues. (Permit to store or ship.)
  • Ventilation is important.

Moderate & Strong Solvents

  • A stronger solvent, ventilation a must.
  • Prints on most uncoated medias
  • May be a bit more finicky than strong solvents and drying could be an issue.
  • Inks may be HAZMAT for environmental and freight considerations.

Color Management – for good output

  • A system consisting of software and instruments to color balance the look of a print when using different inks and/or media
  • Industry standard is ICC profiles
  • Integrated into the RIP or external
  • Not easy, fast or inexpensive
  • Best to purchase RIP with some CMS tools and media from a vendor offering profiles.
  • Color profiling systems read a swatch with known values and adjust what is read to match the intended values as closely as possible when you are printing.
  • More robust Rip software packages provide tolls for onscreen color correction, eliminating the need to go to your application program to make changes—a real time saver!
  • Color profiling systems read a swatch with known values and adjust what is read to match the intended values as closely as possible when you are printing.

Materials are not always what they seem

  • Solvent printers are generally for uncoated films
  • Some of your less expensive films, such as gloss calendared vinyl have chemistry issues. Certain materials hard to print on, must be coated.
  • Material consistency is a key issue, as printing exposes any and all surface flaws.
  • Many good 3rd party options, but know your media and ink vendor

Finishing Options – to laminate or not?

  • Work backwards, or “reverse engineer: from your actual job application
  • How long does your job need to last?
  • Film Laminate – expensive but offers good physical protection.
  • Make sure your film matches the properties of the substrate.
  • Liquid Laminate – excellent protection, low cost. Automated equipment coming on line.
  • Film laminate is on the way out and liquid laminate is on the way in
  • Optically clear vinyl does not exist.

Build your system with the FUTURE in mind

  • Think not only faster, but also wider for step-and repeat jobs.
  • Look for flexibility in available media.
  • No substitute for speed in a computer.
  • RIP should be upgradeable and expandable
  • Much harder to upgrade right after purchase.

Setting up your shop

  • Set up in a clean, dry area. Protect against solvents with epoxy or other flooring.
  • Don’t scrimp on your computers and peripherals.
  • Solvent systems should be properly vented and/or respirator masks used.
  • Organize and label your materials.
  • Provide backup UPS power for lighter peripherals.
  • Allow sufficient room to load and service equipment
  • Maintenance of your system must be a priority.

Choosing a good vendor partner

  • There is no substitute for knowledge.
  • You need to hit the ground running
  • Experimenting takes too long and is costly.
  • Make sure the vendor knows intimately all of the products you intend to purchase.
  • None of the products is perfect yet.
  • Ask about installation and support options.
  • Ask about supplemental training and services.
  • Money spent up front comes back quickly.

Tips to take

  • There is no substitute for knowledge in operating digital production.
  • Get properly trained by your dealer. If they don’t offer training, find another dealer.
  • Digital production has a large percentage of waste. Factor that into your pricing.
  • One of the biggest issues in waste reduction is the loss of time:
    • Inadequate training or job skills.
    • Mistakes
    • Poorly maintained or improperly configured equipment
    • Slow computers

Where to get more information

  • Magazines and other periodicals such as the Review
  • The internet – visit www.bannerflag.com
  • Trade shows and other exhibitions.
  • Other sessions in conferences
  • A good, responsible and knowledgeable dealer.