A phototype plate, representing the picture that is to be transferred, or its negative, is produced: it must be of the same size as the copy is to appear. The printing-ink used in the phototype process, to which any tone of colour may be given, is carefully mixed with a siccative, Japanese gold size being preferred. The quantity to be taken of this liquid depends on the question whether the picture is to dry rapidly or slowly. As a rule, 15 to 18 drops of Japanese gold size to each £ cub. in. of printing-ink may be considered adequate for producing that indelibility which must be attained in most cases. The photographic picture, after having been rolled over with this preparation, is transferred upon the material either directly or by means of transfer paper. The transfer upon ebony or upon any other dark material takes place by means of a white colour prepared in the above manner or of any desired light colour. But the negative required for producing the phototype plate must in this case be converted into a positive, which may be done by the gelatine process.
A thin white paper, one side of which has been prepared with an entirely smooth layer of paste and well pulverised chalk, or in some instances only with a thin layer of paste, must, in dry condition, be so placed upon the phototype plate carefully impregnated with the above ink composition, that its prepared pasted side lies underneath; the paper is then softly pressed with a damp sponge, whereupon the whole is drawn through a press, if possible but a single time. The paper to which the picture has thus completely been transferred is then carefully taken off the plate, and can be immediately transferred on other materials, or it may be kept for the purpose of being transferred at a future time. In order to keep it damp for the latter purpose, it must be placed between damp blotting paper and hermetically packed up. The object to be printed must be fastened in the press, and the transfer paper, after haying been moistened from the reverse, is laid on that part on which the picture is to appear. Some sheets of damp blotting paper are then placed upon the transfer paper, and the whole, together with the usual cover, is drawn through the press once or several times, according to the object upon which the transfer is being made; this done, the transfer paper is moistened with a sponge dipped in cold water until it can easily be detached from the transferred picture without leaving on it any traces of the printing ink.
In order to render the picture completely clear, the layer of chalk attaching to it directly after the act of printing must be removed by means of a soft sponge which has been wetted in cold water. Boxwood blocks are prepared for the process in the following manner: - A quantity of flake white ground in oil, such as is used by painters, must be mixed with a few drops of Japanese gold size, and as much benzine added as will make it possible to work the whole in the thinnest quantity attainable and very swiftly by using a broad brush. When the wood-engraver has finished his task, he removes the white with turpentine or spirit. Upon smaller objects, such as medallions in ivory, metal, wood, etc, the transfer, if executed without delay, can be performed directly from the paper by using a smoothing-bone. This fact is important with regard to .all such objects as are not quite flat but somewhat vaulted. In order to transfer a picture on porcelain, clay, or glass, Pixis takes exclusively enamel colours, and gets them upon the phototype plate by rolling.
If the tone of the picture is to be lowered or strengthened, or if a variety in colouring is desired, either the phototype plate, the transfer or the material, is powdered over with dry colours of the required tint before the enamelling takes place and while the pictures are still damp. This powdering with dry colours may also be applied to pictures which are to be transferred to leather, textile fabrics, metals, wood, minerals, etc. The above-named materials, as likewise painted canvas, wood, metal, etc, may also, after the picture has been passed over, and before the transfer takes place, be prepared in the desired colour by means of oil, distemper, wax, porcelain, and water colours. Every picture, if transferred in the described manner upon wood in several colours or one colour, may, when sufficiently dried, be polished, oiled, and otherwise treated without becoming damaged. Pictures transferred on textile fabrics can be made to stand washing by drawing them, when dry, through a solution of glaire, squeezing and heating them to a temperature of 230° to 270° F. (110° to 120° C).
(2) Take a piece of wood, such as lime, pine, or fir, and get a good, smooth surface on it by planing, glass-papering, etc, being very careful not to leave any woolliness or scratches on its surface after using the sandpaper. The next thing to do is to polish the surface well with ordinary white French polish; but do not finish off with spirits, and be sure and have a good coat of polish on. Now take the picture and lay it on the wood, with picture side to the polish; then take a piece of sponge or cotton wool, and dip it into methylated spirits; brush the back of the paper over with this, being sure it is well saturated, and that there are no air-bubbles left under it. Now put it aside for a time until all the spirit has evaporated and the paper is quite dry, when it will be found to be securely fastened to the wood. Now, to get rid of the paper, it must be gradually rubbed away with water, usjng the tips of the fingers or a piece of soft indiarubber, until the picture appears equally distinct over the whole surface, when the rubbing down is to be discontinued. Now put it aside again for 4 or 5 hours until all the water has evaporated, and then polish with the white French polish in the[ usual way, as if you were polishing a piece of wood.
The white French polish is made from white shellac and methylated spirit.
(3) Transferring Engravings To Paper
The liquid used for this purpose may be made by dissolving l 1/2 dr. common yellow soap in 1 pint hot water, adding, when nearly cool, 3/4 fl. oz. spirit of turpentine, and shaking thoroughly together. Apply the fluid liberally to the surface of the engraving, or other printed matter, with a soft brush or sponge (being careful not to smear the ink, which soon becomes softened), and allow it to soak for a few minutes; then well damp the plain paper on which the transfer is to be made, place it upon the engraving, and subject the whole to moderate pressure for about one minute. On separating them, a reversed transfer will be found on the paper. This transfer will not be equal in intensity to the original, as only a part of the printer's ink is removed. If the print be very old, a longer soaking and more pressure may be necessary.
(4) Henoque's Transfer Process On Glass
Dr. Henoque's method of transferring outlines obtained by means of a stylus on blackened paper on glass is frequently employed, only the outlines are generally executed on paper rolled on cylinders. To photograph these designs, or project them on a screen, it is usual to transfer them to glass without any alteration, the transparency of which renders it capable of being used in either way. Dr. Henoque, after removing the blackened sheet from the cylinder round which it has been rolled, spreads it on a glass, and coats the smoked surface with castor-oil collodion. As soon as the collodion is set, the plate is plunged into water, and, after a moment, a floating pellicle of collodion rises to the surface, bearing the film or smoke and the traced outline. It is next transferred to glass by means of a sheet of paper, and made to adhere with gum applied all over the plate. Great precaution must be taken to fix the edges of the pellicle by strips of paper gummed. When dry, it forms a perfect negative, or may be used as a transparency to project on a screen. In the same way, as Poitevin has indicated, chalk drawings may be removed from paper and transferred to glass. The paper for smoking should be albuminized and lightly gummed.
To smoke glasses on which lines are to be traced with a point, they may be coated with lampblack paint, and the blackened surface afterwards passed over a petroleum lamp flame. The smoke covers over all the inequalities of the coat of paint, and the design may be immediately traced. It can also be taken off and transferred to another glass in the way already indicated. (Photo. News,)