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Progress In Wet Mat Stereotyping

( Originally Published 1927 )

WILLARD S. WHITMORE, of Washington, D. C., in 1881, in his invention relating to paper molds or martices for casting stereotype plates, proceeded as follows: Instead of making his mat up of alternate layers of unsized paper and sheets of tissue paper pasted together and in order to remedy the drawbacks of pulling in wet mats, Whitmore constructed a new composite mold, which was formed of a sheet of unsized paper, covered same with a layer of paper pulp, which had never been set by drying. He formed the plastic pulp by adding to it a watery state, a little glue, gum or other adhesive agent. The water was then squeezed out by pressure, when the pulp was laid upon a heavy piece of unsized paper which had received a coating of paste made of starch, flour or some albuminous substance and allowed to stand a while under a light pressure, so that the paste could combine more thoroughly with both the pulp or plastic and the heavy stereotype paper. The advantage Whitmore claimed for his mat was greater plasticity, toughness, and economy, requiring but one layer of pulp, while the old wet mat required three or four layers of paper.

BENJAMIN B. HUNTOON of Louisville, Kentucky, in 1881 took paper from the common or poorest stock, but of extra thickness; and in order to prepare it for his purpose, he first subjected it to heat sufficient to char or carbonize it, or by dipping it (a sheet at a time) in molten metal, or by baking it (after slight dampening) upon a steam-chest under slight pressure, or by moistening it with acid, and when this moisture had sufficiently evaporated to leave it but slightly soft and pliable it was ready to receive the impression, which was made by passing it through an ordinary printing-press, provided with suitable type, in a cold state, either with or without a paper backing; but if a backing was used it was only intended to assist in removing the matrices from the type. The process of drying was accomplished by means of a steam-heated surface.

GEORGE DAMON and ELIAS PEETS in 1888 produced a metal-faced mat with a papier-mache backing. Their method in detail was as follows: by means of the type they first took an impression in papier-mache, thus forming a matrix. Stereotype metal was then poured into this matrix and an ordinary stereotype plate formed. The plate was then coated with melted wax, and before the wax had entirely hardened, powdered plumbago was dusted over the whole surface. The plate thus prepared was immersed in a copper solution and a film of copper deposited upon its face. The plate was then placed upon a beating table and a sheet of dampened stereotype-paper laid over it, which was beaten into the irregular copper surface. Thereupon a thin coating of pipe-clay was spread over the entire surface, which was then removed from the depressed surfaces (which occur where paragraphs or blanks are found in the type) and into these depressions were then placed small strips of compressed, properly cut stereotype-paper and over the whole were then laid in succession and beaten in several additional sheets of moist stereotype paper. This plate was then smoothed and dried, when the copper coating with its backing of paper, was stripped from the plate and was in condition to be used as a matrix, from which any number of stereotype plates were produced.

CHARLES M. GAGE, of Massachusetts, invented a rather novel mat in 1888. He destroyed the most essential property, the basic fundamental of a paper mat, namely its elasticity. In accordance with his invention his matrix-board was made of sheets of paper composed of vegetable fibre, preferably two or more of these sheets being heated with a solution composed of shellac, borax and water. The sheets of paper were dipped into this solution and thoroughly dried. Hereby the elasticity of the fibre was destroyed. Then there was pasted to this matrix board a finishing-sheet of paper made of a strong long vegetable fibre, which had been coated with paraffine or wax. The non-elasticity of the matrix, permitted, according to Gage, of maintaining a perfect impression for an indefinite period of time.

WALTER B. CARR and AUGUSTUS G. FRENCH, of St. Louis, invented certain new improvements in matrix-boards in 1892. Their invention made to dry a wet mat without heating the type, consisted in forming a matrix of semi-porous blanket, and forming an impression sheet on one of its faces. Their mat consisted in only one sheet of Manila or other ligneous fiber, one side of which was finished, so as to give it the properties of woven paper, while the other side was left in its original semi-porous state, thus making the impression sheet a part of the blanket, which parts up to the time had been applied separately in use. No paste was necessary, as the mat consisted of only one sheet.

Louis G. TIMROTH of Brooklyn invented in 1896 a chemical paste which was to do away with one of the great drawbacks of the wet mat. He claimed that his mat could be rolled for mailing, be stored and kept for an indefinite length of time without liability of souring or otherwise deteriorating. He also claimed that no backing was necessary and that his mat permitted reproduction of the finest possible lines, such as were found in half-tones, which could not be produced by methods hitherto employed. His paste consisted of water, alum, flour, ocher, rosin, ground cloves, sugar starch, gum-arabic and white glue.

When during this period the dry mat cold stereotyping idea was being discussed, the advantages claimed for the same led to many experiments in rapid drying of wet mats on the part of stereotypers who were opposed to the new cold process.

It was tried to produce quickly drying paper matrices by means of easily volatile fluids, for instance, alcohol, but this method had the drawback that the alcohol of the wet mat evaporated too soon, and consequently the mat became dry, before it reached the steam table, whereby it lost its binding power and instead of forming a solid coherent mass, it was loose and liable to be separated sheet layer for sheet layer.

A number of experiments were made to shorten the stereotyping process, one of which was rather novel. In 1884, CHARLES A. SKENE, of Kansas, invented a process to obtain stereotype-plates for printing purposes direct from matrices made by telegraph—or type-writing machines, and thus obviate the necessity of having to prepare type-forms in order to obtain a cast, thus saving the' time, labor, and expense of composition, distribution, and make-up that are necessary pre-requisites to the operation. In order to carry his process into operation, Skene took a thin sheet of soft paper and coated it evenly on both sides with a brush that was dipped into a pasty mixture of glycerine and plumbago. When the paper had thoroughly absorbed the mixture, it was passed between heated rollers until its surfaces became perfectly smooth. The paper so prepared was placed in a common type-writing machine, and the writing proceeded with as upon ordinary paper. Skene expected the types to make impressions on the paper sufficiently deep to form a mold or matrix in which a stereotype plate could be cast in the ordinary manner for use on an ordinary printing-press. He stated that "it will be obvious that a telegraph printing machine may be thus employed in preparing the mold or matrix, and operated from a distant point, which will be found of great practical utility." His hopes were not realized and no practical use was made of his invention.

This idea of typewriting and also of linotyping directly on a prepared paper matrix has been followed up by different inventors; as late as 1922 machines for this kind of work were invented and patented. It appears, however, that for many years to come such attempts will prove futile, because of the many billions of dollars tied up in equipment which hardly can be scrapped before such new ideas have been tried out in practice of a score of years and have proven beyond a shadow of a doubt the claims made for them by their enthusiastic inventors. Machines have been invented to do away with the use of type altogether, by punching the types on some sub-stance which acted like a matrix and became a mold from which stereotype plates could be cast, for instance, punching upon teak wood. This process was impractical as it did not permit of correction.

J. G. RIVETT, Mechanical Superintendent of the Western Newspaper Union, is the inventor of the Rivett patent flong machine. This machine produces in a continuous automatic manner, stereotype wet mats laminated in any number of sheets at one operation. It is capable of turning out from 300 to 400 completed wet mats per hour. This machine is made in various numbers of units to produce wet mats in any number or combinations of laminations. However, the price, between $5,000 and $6,000, has so limited the sale of this machine that there are not more than five of them in use in the United States.

W. C. HANDLEY, New York and Cleveland stereotyper, is also the inventor of a wet mat making machine, and has sold many of his machines at about $1,500. With this equipment the roll must be re-run for each extra tissue. How-ever, it produces a very fine wet mat and the price being comparatively low, more of these machines were in use at one time.

ZEB. E. AIKEN and DANK L. RAINER of Tulsa also invented a wet mat machine embodying a plurality of bed rollers.

It would be going too far for the purpose of this booklet to record the many different materials matrices have been made of, especially so as no materials outside of clay, plaster of Paris and paper have proven to be of any practical value or to have been used outside of the foundries where they were invented.

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