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The Dry Mat, Or Cold Stereotyping Process

( Originally Published 1927 )

Just as the deficiencies and shortcomings of the plaster of Paris process led to the invention of the papier-mache process of stereotyping, thus in due time the drawbacks of the latter made the invention of a better method a necessity. The quality of the work done by means of the wet mat method could hardly be improved upon, therefore the activities of practical stereotypers and inventors were directed towards obtaining equally excellent printing results, doing away, how-ever, with the many drawbacks encountered in the use of the wet mat process.

The shortcomings of the papier-mache or wet mat method were few but far reaching. This steamtable, or hot process of stereotyping employs "wet mats" which are generally handmade in each plant from day to day; a series of special matrix papers and high grade tissues are pasted together with a mixture of flour paste and gum arabic to make these wet mats.

In almost every newspaper plant the preparation of wet mats and especially of such paste comes under the duties of the foundry superintendent, and these experts usually have their own special and jealously guarded "secret" paste formula. (Ged and Stanhope exercised the same secretiveness). There were, however, a number of printing supply concerns who made and sold secret pastes to the trade, under various names such as: pulchre paste, ivorite, nickello, electroline paste, etc., etc. It was to a certain extent due to this secretiveness practiced in practically every plant possessing a stereotype foundry that stereotyping was about the only phase of newspaper production which had not kept pace with 20th century progress.

Owing to the fact that all pastes used for the purpose of uniting the different paper layers of the wet mat have a tendency to sour and to mould, it is not practicable to prepare wet mats very far in advance.

Then again, uneven pasting as well as fermentation in the paste often causes wet mats to blister and blow up when they are molded and cast.

DEFICIENCIES OF THE WET MAT. To dry out the paste and the paper, the form of type with the wet mat, has to be subjected to a high temperature, generally done on a steam-table. It is obvious that the mat and the type cannot be separated until this mat has been thus hardened by heating and in this operation the type is necessarily heated also. It is in this particular that the main objection to the wet mat process exists, the heating of the type being a positive source of destruction to the type. When needed for "make-overs" for later editions, the superheated forms must be rapidly cooled, subjecting them to uneven expansion and then contraction, soon ruining even the most expensive foundry type.

The stickiness and bother of the "paste pot" work and above all the inhuman necessity of the stereotypers working in an atmosphere of intense heat, thereby endangering their health, are foremost arguments against the use of wet mats.

The comparative slowness of the wet mat process is also objectionable, in newspaper work, where the gain of time, after the copy is received, of preparing the matter for the press, is of greatest importance. Four to seven minutes of valuable time is consumed in baking the wet mats on the forms.

In spite of the fact that with the wet mat steam-table process of stereotyping such bodily inconvenience is suffered by the workmen, such invaluable time is lost, and great expense incurred, newspaper publishers have felt that as long as there was nothing thoroughly proven to be better, more rapid than, and still giving the same quality of printing obtained with the old wet mat process, they were justified in sticking to the old method, and in not discarding their steam-tables.

But in the meantime fertile minds were at work on the problem of making a matrix, eliminating the paste pot, the steam-tables and their attendant vices, and saving invaluable time in the getting out of the daily newspaper.

The end result of all this labor and experimenting is the DRY MAT, ENABLING COLD STEREOTYPING. Up to the advent of the present day dry mats, about three years ago, dry mats were made upon a paper machine in one piece and not pasted together as is the case with the wet mat. They were beaten in with a brush in a cold state and no steam was used. Owing to inherent deficiencies of these dry mats themselves, the dry mat idea did not make converts very rapidly. Although very few foundries bothered to pet these dry mats enough to be able to use same, the idea was conceded to be a good one, the time saved also looked upon as a very favorable factor, but the ever varying thickness of the dry mat, the proclivity to blistering, buckling, chipping and pulling, the uncertainty of the proper humidifying, were not overcome until many years afterwards, and after innumerable experiments and setbacks.

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