Digital Book Printing
The following is presented in association with CAP
Ventures, the leading consultant to the digital printing industry.
- Industry Trends Favoring POD
- Applications for POD
- The Cost of Digital Printing
- How Digital Printing Works
For publishers, the question of whether to publish a book has always been
partially decided by printing costs. Generally speaking, traditional offset
printing incurs set-up, plate-making, and bindery wastage costs that make it
uneconomical to print fewer than 750 to 1250 copies. If demand for a new or
out-of-print book does not exceed this number, the publisher cannot make a
profit using offset printing.
Needless to say, there are many otherwise viable titles whose demand
falls under this minimum number, resulting in either high unit prices
or unavailability. As will be detailed below, digital printing does
away with this unfortunate equation.
Industry Trends Favoring Print-on-Demand
In addition, many industry trends are making digital printing more
attractive for publishers. They include the following:
- Booksellers' increasing focus on their own profit margins
(especially the large chain stores) is driving up the return rate for
- Traditional production, shipping, and warehousing costs are rising
with the general inflation rate despite a high level of automation by most
- Prices for books, especially trade books and college textbooks, may
be increased only slightly before consumers balk.
- Most large publishers, in this rapidly consolidating industry, have
put huge amounts of good will and debt on their balance sheets, which in
turn is putting added pressure on profits.
- Publishers' need for investment capital to explore the use of new
media (e.g., CD-ROM, Web publishing, eBooks and diskettes) put additional
pressure on profits.
- The growth of publishable material continues at a rapid rate--more
authors, more subjects, and more specialized titles with inherently
smaller targeted markets that in turn create a demand for shorter run
- The dramatic increase in online booksellers (virtual bookstores)
with databases containing millions of titles has increased demand for
backlist and out-of-print books. Forecasting demand for titles sold
through online booksellers is an almost impossible task.
- The widespread adoption among publishers of computer-to-plate and
computer-to-press production processes means that they can send content
files, based upon open standards, to just about any type of printer or press.
- The increase in the use of eBooks (i.e., handheld electronic devices
used to read copyrighted content downloaded from publishers' Web sites) by
professionals and consumers means publishers will standardize on PDF
(Adobe's Portable Document Format) and/or XML (eXtensible Markup Language)
file formats for archiving their content.
Applications for Print-on-Demand
For publishers, there are five primary areas in which digital or on-demand printing can beat offset printing in both cost and convenience.
A benefit of digital printing is that the process of preparing a document for
printing is nearly the same as that of putting it in e-book format. This means
that few extra costs will be incurred when it is released in the latter format.
- Database Custom Publishing. This is most commonly found in college
textbook publishers, reference publishers, trade publishers (especially
publishers of softbound computer book and manuals) and certain STM
(scientific, technical, and medical) publishers. Characteristically,
content in database custom publishing is:
Many of these publishers are finding that on-demand printers, in addition
to offering the advantages of digital print (see above), offer useful
value-added services. These can include scanning and file conversion,
file management and storage, component cover printing, binding, and
finishing, as well as kitting and fulfillment.
- owned by the publisher;
- organized in a variety of ways;
- of a timely nature; and
- usually branded for the end user in some way.
- Keep-In-Print Programs. Publishers rarely benefit from allowing a book to go out
of print. Almost without exception, it is offset printing costs that decide the
matter for them. With new demand for out-of-print titles being driven by online
booksellers, who can take orders for literally millions of titles whether or not
they're in print, many publishers are turning to POD to bring titles back from the
Leading keep-in-print candidates are books that have timeless or classic qualities,
within the categories of trade books (fiction and non-fiction), college textbooks
(mainly in the subjects of English, history, modern language, and the social
sciences), religious books, and certain STM books.
Because many keep-in-print books predate electronic composition and page layout
methods, high-quality scanning is required to put them in an electronic file format.
- Short-Run Publishing. The vast majority of U.S. publishers are
small or regional publishers whose book lists are filled with short-run
books. Digital printing makes even shorter print-runs or reprint-runs profitable,
enabling publishers to serve their niche markets better and take more risks on
authors of unknown potential.
- Course Packs. CAP Ventures estimates that in total, the course pack business
represents about $1 billion in annual sales. This business is spread among on-demand
printers (who also offer copyright clearance services), campus bookstores and copy
centers, off-campus copy shops such as Kinko's, and traditional textbook publishers.
On-demand printers are ideally suited for this kind of work, which involves
significant and ongoing document preparation and updating, the printing of
precise numbers of copies, and delivery on short notice.
- Prepublication Copies. All publishers need to produce prepublication copies.
These are called, variously:
The production specifications for most preproduction books call for a
perfect-bound book with black and white interior and two- to four-color cover.
This is the digital printer's most cost-competitive format. These copies can also
be shipped directly to reviewers or potential customers by the printer, saving on
- Review copies. Publishers send these to book reviewers to secure
reviews for the title before its publication date. The review copy must
look as close to the finished book as possible. The number of copies can
range from 15 to 500.
- Sample or complimentary copies are usually produced in the same quantity
as review copies and are used to secure major sales; e.g., school systems,
college adoptions, large chain stores, corporate bulk sales, and sales to book
clubs. Again, as with review copies, sample copies need to look like the actual
book and be printed quickly, in small numbers.
- Trial editions (sometimes called pilot editions in El-Hi) are intended to
test the content of the book, usually within a group of learners, so that
further revisions may be made.
The Cost of Digital Printing
Printers' prices vary, and costs are coming down all the time. As a general
rule, however, as of late 1999, the digital printing of a trade-sized book costs approximately:
This means a 300-page perfect-bound paperback book would cost approximately $5.50 to print. This is
regardless of quantity: unit cost is the same for one copy as it is for 10,000.
Offset printing therefore becomes a cheaper option than digital printing at
quantities around 750-1250.
- 1.5 cents/page of text (black & white)
- $1.00 per cover (four-color paperback)
- $5.00 per cover (four-color hardback)
How Digital Printing Works: A Technological Overview
The following is based on the book The Print-on-Demand Opportunity: Technology,
Products & the Business, published by CAP Ventures and available for purchase
at their Web site.
Digital book printing involves three primary types of systems: front-end, imaging,
In book publishing, it is common for the publisher to handle design (cover,
typesetting, layout, etc.) and any necessary scanning. Publishers are also
generally capable of putting the final document in the appropriate digital format,
such as PDF (Adobe's Portable Document Format), so that very little further
manipulation is needed before printing.
The hardware and software tools necessary to do this kind of document preparation
can be considered front-end systems. Though most print-on-demand (POD) firms are
certainly equipped to typeset, design, scan, and convert documents to printing
languages, the tools they use are by no means unique to them. The same tools are
used by publishers, traditional offset printers, and even individuals.
Front-end systems that are more unique to POD firms have to do with document
storage, inventory, and ordering. Digital printing firms are competitive in
large part because their technology allows them to automate otherwise
time-consuming, labor-intensive processes and avoid expenses involved with
physical storage and manipulation. Their primary front-end systems are:
- Software to bring clients into the process. Through networks, the Internet,
and electronic media, clients should be able to order and distribute books
from their own workstations. They should have access to the printer's document
management library to view proofs and update files.
- An electronic library. A library database receives and stores documents in
a variety of formats, including scanned file formats (like TIFF),
page-description-languages formats (like PostScript and PCL), and software
application file formats. Searches can be performed using key word, title,
subject, date, ISBN, job number, etc. Electronic libraries must allow for
quick and cost-effective retrieval of print-ready documents and related
The demands of a digital library, in equipment and human expertise, are
large. Storage media can vary from removable kinds (e.g., tapes such DATs,
optical disks such as CD-ROMs) to large, networked hard drives. The software
needed to manage document storage and retrieval on such a large scale, and at
high speeds, is very sophisticated. There is also the very important matter of
backing up all data on a daily (or indeed continuous) basis and storing it
- An automated process. The whole point of POD is that documents can be
printed as needed. This decreases or eliminates warehousing and related costs
and labor, but it also results in a printer receiving more small orders. For
example, a digital printer might receive orders for 10 different books, 1-4
copies of each, and be expected to print and ship them all within 48 hours.
This is beyond the ability of an offset printer, but it is the bread and butter
of POD printers. Therefore they must automate the ordering, retrieval, printing,
and packing processes as much as possible.
Integrated front-end systems maximize throughput by distributing jobs to available
networked printing devices, organizing and queueing these jobs such that the
printing devices are working as continuously as possible, and collecting
information that can be used by management to analyze the production process and
automate accounting and billing.
For book printing, most POD firms use electrophotographic technology that is
essentially the same as that used by a desktop laser printer. The key advantage of
this technology is that it allows each printed page to contain a different image.
This means that unlike a typical offset press, which must manufacture one plate
per page, a POD printer can print an entire book using only one re-imageable plate.
This saves on costs and makes it economically viable to print one book at a time.
POD imaging systems can be either sheet-fed (use individual pieces of paper) or
roll-fed (use a roll of paper). Some use laser systems, some use LED
(light-emitting diodes), some use dry toner, some use liquid toner. There are
dozens of minor variants. Simplified, the electrophotographic imaging process is
- Charge--The photoconductive roller or "drum" receives a uniform electric
charge from wires next to it.
- Expose--The laser or LEDs create a latent image on the photoconductive
surface. Where the light beam strikes the drum, the charge is altered.
- Develop--The surface of the photoconductor rotates past a developing
station where toner (ink mixed with a binding agent and electrically sensitive
"carrier") is attracted--and sticks--to the image area on the drum.
- Transfer--At the transfer station, a strong and opposite electric charge
draws the toner away from the rotating drum onto the paper. This opposite
charge can be held by the paper itself or by a device on the other side of
- Fuse--Heat and or fused pressure are used to bond the toner to the paper.
- Clean--To prepare for the next image, the photoconductive drum is cleaned
of any remaining toner.
The imaging process yields pieces of paper with print on them. The finishing process
involves the following:
(See How-To/Printers/Binding for a
description of various book bindings.) Other finishing services include:
embossing, die cutting (pages cut into special shapes), lamination, shrink
wrapping, insertion (e.g., CD-ROMs), and drilling holes for binders.
The machines used to complete these jobs need not be technologically advanced.
Theoretically, they can be the same ones used by traditional offset printers.
The POD printer, however, has to be able to finish very short runs
economically--i.e., both quickly and with as little human intervention as
possible. This rules out most "offline" (separate, free-standing) finishing
Those POD firms that can afford them, therefore, invest in machines that do as
much of the printing and finishing work in-line (in one continuous process) as
One example of this kind of technology will give an idea of its complexity (and
expense). The Bourg Book Factory is an automated in-line finishing system that
combines technologies from Xerox, Roll Systems, and C.P. Bourg. The process
starts with the DocuSheeter from Roll Systems, which cuts roll paper stock into
sheets. These sheets are then fed in-line into a Xerox DocuTech. The DocuTech
prints the pages 4-up on the 9" x 12" sheets. The printed sheets then exit the
DocuTech and are fed into a choice of finishing devices from C.P. Bourg. These
include Bourg's High Capacity Stacker; the Bourg Perf Rotate Fold, and the Binder
BB2005, which produces perfect-bound finished books in sizes ranging from 5.5" x
8.5" to 9" x 13". The resulting signatures and wrap-around 4-color covers are then
bound into final assembled books/booklets and 3-side trimmed for delivery. For
applications not requiring perfect-bound books/booklets, sheets can be bypassed
in-line directly to the Bourg Document Finisher, which produces saddle-stitched
documents. The Bourg Vacuum Feed Cover Station provides covers for the