The Flipback - challenger to the traditional eBook

The advance of technology is relentless. With the introduction of "Flipback" technology it may soon begin to erode the domain of traditional eBooks.

The Flipback format is a sideways-bound book with lie-flat binding and is sized to fit in a shirt pocket and optimized for easy one-handed reading.
Flipbacks are comprised of pages rather than bytes and pixels. Their compact size is made possible by the printing of words on wafer-thin onion paper, the same type of paper traditionally used for the printing of Bibles. Like the eBooks it may eventually replace, the Flipback is easily portable but, unlike eBooks, it needs no external power (except for physically turning the pages).

Could this invention kill the entrenched traditional readers like Kindle, Kobo, Nooks, etc?" Only time will tell if consumers are willing to adopt this innovation in reading technology.

Paper size and weight conversions

In North America, the default paper size is "Letter" size while outside North America, the default paper size is A4.

ISO 216 - Standard Metric Paper Sizes
Standard North American Sizes
Paper weights

There are two terms commonly used to describe paper weight:
• Basis Weight
 The basis weight of a paper is based on the weight of 500 sheets,
 measured in pounds, in that paper's basic sheet size. Note that the "basic sheet size" is not the same 
for all types of paper which makes comparisons of weight between different papers difficult.
• Caliper 
Caliper refers to the thickness of a sheet of paper measured with a micrometer and expressed
 in thousandth of an inch. Paper caliper should not vary more than +/- 5% to 7% 
within a sheet. Generally, there is a relation between caliper and basis weight in that 
the greater the caliper (the thicker the paper), the greater the paper weight. But not always.

Darker colored boxes represent the
most common paper weights for that category.This Table was compiled by Micro Format, Inc., Wheeing IL. Used with permission.

The Wayback View - German printshop advertising - circa 1926

German culture is noted (outside of Germany) for its engineering excellence and its lack of humor. These examples of printshop advertising posters fall into another category - graphic design excellence.

(My very rough translations)

Good print advertising and offset book printing.

Rough poster prints
The offset printing chosen by professionals. Offset papers and cartons.
Imitated but not equalled.

If your advertising needs are putting on the squeeze - we can help.

The paper problem - no specifications

Typically paper - the most used printing substrate - accounts for some 30-50 percent of the overall print project cost. And despite the fact that it is also often the most expensive component of the final presswork it's surprising that there are no published standards, specifications or trade customs in the paper industry.

The assignment of a particular grade to a quality category and the establishment of sales policies are made by each paper mill based on its own internal evaluation of its products relative to those of its competitors. 

That makes direct, objective, competitive comparisons between different papers virtually impossible. 


The color of paper is identified using adjectives like "cream","natural", "white", etc. rather than objective definitions such as the CIEL*a*b* coordinates that printers use. Again, there are no specifications or tolerances provided by mills as to the consistency of a specific paper color either through the stack, roll, or when the same brand is supplied by mills located in different regions.

The brightness of the sheet is one common measure of distinction. It is measured by comparing the amount of light reflected by the paper surface to the amount of the same light reflected by the surface of magnesium oxide established as the standard of 100%. A common term used in quoting the measure is “G.E. brightness,” although G.E. no longer manufactures the measuring instrument. "Brightness" is also not a measurement that printers or buyers can measure themselves. Even though variation is part of every manufacturing process, there are no defined tolerances for paper brightness.

There are no specifications or tolerances or even notification of optical brightener agent content. This has become a major issue as the mills have mostly switched from clay fillers to calcium carbonate. This problem has resulted in the fact that papers today, for the most part, no longer meet the ISO 12647 specification. Papers with optical brighteners are impossible to visually match between printing technologies which can cause severe disconnects between proof and presswork as well as greater color shifting as presswork and proof are viewed under different lighting conditions.

"Caliper" defines the thickness of paper, measured in thousandths of an inch, which can also be expressed as a point size - e.g. If the caliper of a paper measures .009 inches it is a "9 point" stock. As paper caliper varies, presswork color may also vary. But again there are no defined tolerances for paper caliper either through the stack, roll, or across the width or length of the sheet.
If the sheet metal used in car manufacturing was specified and toleranced with the same technical rigor as a sheet of paper is for print manufacturing - the cars would likely be undrivable.