What Is Deep Etch Offset ?

I was looking through the ROC Taiwan Post website
https://www.post.gov.tw/post/intern...77&keyword=% and
noticed that the printing process for the Tower definitives
was by deep etch offset and this process included
an engraver apparently
Engraver for offset stamps?
For typography yes but for offset?



Here is the only one I have from that set and it looks
like any other normal single colour litho/offset stamp.

Lithograving, I was totally unfamiliar with this term, but came across its definition purely by accident earlier today.

Collector Robert Harm describes it in his philatelic glossary as follows.....

Deep etch offset: This is a form of lithography using plates on which the printing areas are etched below the surface to compensate for wear, or to prevent blurring on rough paper. This process is widely employed in the stamps of Taiwan.

The source of this information is the July 2016 issue of the newsletter of the South African Stellenbosch Philatelic Society. I hope it helps. There is always something to learn, isn't there!! GLENN

Thanks Glenn.

plates on which the printing areas are etched below the surface

That is very similar to indirect recess isn't it?

Interesting topic and responses. Thanks for posting!

Lithograving, I would prefer not to start making comparisons between indirect intaglio and deep-etch offset on this thread, as I feel that it will only serve to potentially confuse matters even further. They are separate processes and should remain so in our minds and our descriptions. Personally, I do not consider them sufficiently similar to enable a true comparison to be made, but admit that I kind of know where your thought process is coming from! GLENN

I agree Glenn, different processes of course
but this deep etch offset is not
your normal offset.

I mean what is one basic description of
offset, lithography, offset/litho, letterset etc ?
They are all surface printings versus recess/intaglio/engraving/gravure etc or relief such as typography/letterpress.

Letterset, or typography is not a planographic printing process.

The term "deep tech offset" makes no sense to me. If I is deep etch, it is a recess printing. If it is offset, it is a planographic printing process. I appreciate Glenn's explanation from the source, but that does not make term, or process understandable.

Bookbndrbob: I had tended to agree with you. However, Google allows you to enter the word "define" followed by a colon and your search term. In so doing it returned several responses, including that at https://www.merriam-webster.com/dic.../deep%20etch

"Definition of deep etch: the etching of an offset printing plate to such a degree that the printing area becomes slightly recessed and thereby productive of sharper definition and longer runs."
This recognises the intaglio aspect of the deep-etch method when stating that it is "slightly recessed". Although not stating so, it is also implying that the depth of the recesses are not enough to create a raised impression on the printed substrate.

Website http://printingknowledge.com/old_pr...king-offset/ states

"Deep-Etch: The deep-etch offset plate is different than other offset plates in that the image area is slightly below the surface of the plate. The etching allows the plate to carry more ink than surface coated plates. The plate is made from an aluminum, zinc, or stainless steel base. Film positives are used to produce the image on the plate. After the plates are exposed and processed, the unexposed or image areas are etched and chemically treated to form a copper finish. The etching and chemical treatment makes the image areas more receptive to ink. The exposed areas (non-image areas) remain receptive to water (fountain solution). Deep-etch plates have a much longer press life than surface plates and so they are used for press runs of 500,000 and over. They are not used for short runs because there are many other types of plates that are more economical to produce for short runs."
(Collectors talk of surface printing, i.e. letterpress, but the author here when talking about "surface plates" is referring to offset plates, i.e. planographic.)

The book "Dictionary of the Printing and Allied Industries" by F.J.M. Wijnekus and E.F.P.H. Wijnekus (1967 through to 1993 edition) states on page 182

"Deep-etched offset plate, deep-etch plate: Offset printing plate with an intaglio image filled with a substance that attracts ink to make it planographic."

Despite our uncomfortable feelings regarding this process, it is clear that the printing industry is more than familiar with this method and recognises its cross-over between pure intaglio and the planographic method.

GLENN

Did we have the "dry-offset" discussion yet???

https://www.britannica.com/technology/dry-offset

Glenn, these statements by the sources make perfect sense. And, the process is exactly what I had imagined it to be.

Somehow, the process seems to be mis-named. If it were "shallow-etched offset", that would seem most appropriate.

bookbndrbob, you mentioned that Letterset, or typography is not a planographic printing process.

Actually I wrote that relief such as typography/letterpress.

Letterset and letterpress, two different printing processes.

See Galeoptix's link about dry offset.


I do agree with you about calling it shallow-etched offset.

Glenn thank you for finding all those definitions which clears
up somethings but I still have difficulty understanding
this process.
Lets face it the printing business like any other is there to make
money and if they can find a cheaper way of doing things then
they will do so.
The only benefit I can see about this deep etch offset is
this Deep-etch plates have a much longer press life than surface plates and so they are used for press runs of 500,000 and over.

If so then why isn't it used throughout the stamp printing
business. Or is it?

Anyway it's a great discussion.

Sorry lithographing, I stand corrected. Dry offset is another "new-fangled" technique.

Lithograving, The process of deep-etch offset is not openly referred to by stamp printers, or we would have been familiar with its name in new issue stamp listings before now. I doubt that the Taiwanese printer is the only one using it though, as it is not their own process but simply a printing industry process that is used by them. Rarely would a printer use its plate making method as part of the process name, hence listing simply stating "offset" or "litho".

Let's not forget that traditionally offset was always used for smaller print runs and gravure for the large runs. With smaller and smaller print runs being ordered by postal administrations the use of gravure is rarely encountered these days (yes, there are a couple of exceptions). Using deep-etch offset for Taiwanese longer print runs is probably much cheaper than using expensive gravure presses.

Sorry to be controversial, but I disagree with introducing "shallow-etch offset" as a term. There is already a shallow-etch offset, namely the normal / traditional offset printing plate that barely has any depth to it. The deep-etch offset plates ARE deep, but only when correctly compared with normal offset plates, NOT when compared with intaglio.

GLENN