US465833A - Joseph cavallt - Google Patents

Description

UNITED STATES PATENT OFFIcE.

JOSEPH OAVALLI, OF LONDON, ENGLAND.

METHOD OF O'RNAMENTING IRON TABLETS.

SPECIFICATION forming part of Letters Patent No. 465,833, dated December 29, 1891.

Application filed April 17, 1891. Serial No. 389,347. (No specimens.) Patented in England June 4, 1890, lilo. 6,787.

To etZZ whmn it they concern:

Be it known that I, JOSEPH OAVALLI, lithographer, a subject of Her Majesty the Queen of Great Britain, residing at 192 Kennington Park Road, London, in the county of Surrey, England, have invented certain new and useful Improvements in Treating Iron Tablets for Ornamental and Advertising Purposes, (for which I have obtained a patent in Great Britain, No. 6,787, bearing date June 4,1890,) of which the following is a specification.

My invention relates to an improved method of treating iron tablets for ornamental and advertising purposes generally, and is term ed by me litho-smalto iron, and by the means hereinafter explained I am enabled to permanently fix upon said tablets any subject that can be produced upon or by a lithographic stone, such as maps, plans, sketches, or drawin gs, in any color or colors.

In carrying my invention into effect, I draw or sketch upon a lithographic stone, or use a lithographic stone upon which is already drawn or sketched the subject desired to be reproduced upon the iron tablet. I then procure two pieces of cardboard, preferably of the same size as the iron tablet. Each of said cards I coat upon one side with a solution of gum-arabic, or any other suitable gum of a like nature, and place them aside to dry. The iron tablet intended to receive the design previously drawn upon the stone I coat upon'one side with a suitable enamel, which may be of any of the best kinds in general use for that purpose. \Vhen said enamel is set and hard and the gum upon the cards is dry, I pass the latter between press-rolls so as to insure a perfectly true and even surface upon the gummed or glazed side thereof. Upon one of said cards I take an impression of the subject drawn upon the stone previously mentioned, but in substitution of the usual ink I use a preparation composed of two parts, or thereabouts, of crystal copal-varnish, and one part, or thereabout, of a naphthaline or spirit Varnish, commercially known as copzalina. Vith this preparation I ink the stone in the usual way. The impression taken upon said card beisg purely superficial, by reason of the gum upon the card preventing the inking preparation from soaking thereinto, every dctail of the imprintisperfectly sharp and clear.

Said card is then placed upon the iron tablet with its unprinted side next the enamel and -both subjected to pressure, which imparts to the enamel upon the iron the subject exactly as it appears upon the stone,every line being perfectly clear and distinct. The tablet is then laid aside until the imprint thereon is partly set, or until it becomes what is technically known as tacky, and by reason of the high volatility of the preparation used as ink a very few minutes will suffice for it to acquire this condition, and in the hands of askilled operrator this is easily gaged.

Having previously decided upon the color or tint intended to be used, I procure this in very fine powder (which must in all cases be a mineral production) and dust this over the enameled imprinted tablet, or plate previously described, the colored powder adhering only where said imprint exists. The superfluous powder is then carefully dusted off,'

leaving the inked impression only perfectly covered with the color, every detail being still clearly preserved. The tablet or plate is then or at any subsequent period, placed in a furnace and heated until the colored imprint has become incorporated with the enamel, when it is removed from the furnace and put aside to cool, and when cold presents a perfectly smooth and translucent surface, fully and clearly showing every line and detail of the subject without causing the imprinted and colored matter to become blurred or otherwise injured.

In order to facilitate the operation and economize time, I find in practice that the best method of carrying out the operation is as follows: Given that the desired subject is upon the stone and the two cards glazed, dried, and rolled and the number of iron plates or tablets intended to be treated are enameled and ready for use, I take an impression from the inked stone upon one card and lay it aside. I then reink the stone and place the second card thereon and take an impression upon that in the following manner: Upon the back of the second card when upon the stone I place the back of one of the iron tablets so that its enameled face is uppermost, and upon this I place the first card with its imprinted side next the enameled face of the tablet; and to facilitate the operation and prevent possible labor.

rupture of the enamel I place upon the top of the latter card a thickfi'annel or felt, preferably of the same size as the card. The whole may then be subjected to pressure in the same manner and preferably by the same means as lithographic printing generally. By this means the one pressure from the machine gives to the bottom card an imprint of the matter upon the stone and the iron tablet an imprint of the matter upon the upper card. The upper card is then removedand the tablet taken away and dusted with color by a junior operative in the manner previously described. The bottom card may now be removed from the stone and laid aside in the same manner as the first. The stone may now be again reinked and the card that was first printed again placed upon the stone in the same position as before, suitable register being employed for this purpose, as in lithographic printing generally. An iron tablet is then placed upon this face upward and the remainingcard placed thereon face downward, as before, and the operation repeated until the Whole of the tablets are printed and dusted with color. By this method I am enabled to perfect a saving in both time and It is not necessary that the tablets should be put into the furnace immediately after being dusted with the color in the manner described, but may be so treated at any subsequent date, even to the extent of months, if needed, care of course being exercised that the matter thereon does not become scratched or injured, so that a further saving of time is efiected by furnacing a number of tablets together instead of one at a time.

Iron tablets treated as described are perfectly water-proof, and the designs imprinted thereon as durable and immovable as the designs or patterns in ceramic and similar glazed or enameled earthenware, and any design or pattern may be so produced upon and within the enamel of the iron tablets in the manner described, and where necessary a picture or design with more than one color therein may be reproduced upon the enameled iron by repeating the described operation for each color, in the same manner as lithographic printing upon paper.

Having now fully described my invention, what I claim, and desire to secure by Letters Patent, is-

1. The herein-described method of ornamenting iron tablets, which consists in first drawing the desired design upon stone, then taking the iron tablet, which is suitably enam eled, and pressing upon the surface of the said enameled tablet a card-board sheet the surface of which is gummed and upon which is the design which has been transferred from the lithographic stone, then applying colored dust thereto, and subsequently baking the same, substantially as described.

2. The herein-described ink for the purpose specified, consisting of a preparation composed of crystal copal-varn'ish and copzalina, in substantially the proportions specified.

In witness whereof I have hereunto set my hand in presence of two witnesses.

' JOSEPH (JAVALLI.

- Witnesses.

GEO. THos. HYDE, S. J. EARL.