US1025760A - Electroplating process. - Google Patents

Description

UNITED STATES PATENT OFFICE.

IiRAIhTC-IS J. MOELHONE, 0F JERSEY CITY, NEW JERSEY.

ELECTROPLATING PROCESS.

No Drawing.

To all whom it may concern:

Be it known that I, FRANCIS J. Mo- ELHoNn, a citizen of the United States, and a resident of Jersey City, in the county of Hudson and State of New Jersey, have invented a new and Improved Electroplating Process, of which the following is a full, clear, and exact description.

This invention relates to electroplating or electrotyping, and the object of the invention is to provide an improved process for treating the molds or cases, which will improve the quality of the work and hasten the electroplating operation.

The present invention may be considered an improvement on the process covered by my patent for electroplating process No. 973,951, granted October 25, 1910; and concerns itself especially with the manner in which the agent is applied.

The invention consists in the process to be described more fully hereinafter and particularly set forth in the claims.

In practising the process according to the present invention, an impression from the engraving or type is taken in a case of wax or similar plastic material covered with graphite or a similar conductive facing. After the impression is taken the case is cut down and built up in the manner well known in the art. The face of the case is then dusted over lightly with dry graphite. I then treat the face of the case with a solution having the following composition: 1 gallon of water, 2 lbs. of graphite, 100 grs. of pyrogallic acid. This mixture may be applied by means of a brush or a forcepump. The action of the acid appears to be beneficial because it tends to prevent the formation of bubbles on the face of the case.

It seems that the great pressure to which the case is subjected in taking the impression of the type, has the effect of bringing to the surface lighter oils such as paraflin. This fact was noted in my previous application referred to above. The acid dissolves these lighter oils and frees the face of the case from grease. If ink should be left adhering to the face of the case by the type, this ink will also be dissolved off by the acid. After treating the case as described above, it is rinsed oif thoroughly in water to remove the acid and foreign substances in solution; and the graphite that does not firmly adhere to the case. The case is then ready to be immersed in the plating bath.

Specification of Letters Patent.

Application filed May 11, 1907. Serial No. 373,046.

Patented May 7, 1912.

The presence of the graphite in the solution is advantageous as it tends to deposit in a uniform coat upon the face of the case.

Other acids which may be used are tannic, gallitannic or gallic acid, or any of the acids of the benzin series, or carbocyclic series.

If the depositing of the metal in the electroplating bath seems slow, it may be hastened by treating the face of the case with the well known solution of blue-stone and iron filings, just before immersion in the plating bath.

I have discovered that the composition of the plating bath is of unusual importance when used with cases treated with acid as described above. I produce the best effects with a solution of the following com position: 1 gallon of water, 23 ounces and 205 grains of sulfate of copper or blue vitriol, 6 fluid ounces of sulfuric acid or oil. of vitriol. The specific-gravity of this mixture will be about 17.5 Baum. The solution may be made more or less concentrated by changing the proportion of water, but I find that the proportions of the copper sulfate and sulfuric acid relative to each other should remain unchanged. In practice the acid solution with which the cases are treated can be used repeatedly. However, it will be found that the solution becomes contaminated with grease and ink to an undesirable extent. WVhen necessary, the mixture may be allowed to stand until the black lead settles and the liquid may be drawn off. Then more liquid may be added to the black lead to be used again on the cases.

It will be found that wax will accumulate in the mixture when used again and again as suggested, and this tends to cling to the face of the case, preventing the production of perfect plates. From time to time this wax may be removed by heating the mixture, which brings the wax to the surface. This scum formed at the surface is then removed by skimming.

I wish to emphasize the importance of the rinsing which the case is given before immersion in the plating bath. This rinsing should be thorough so that all of the acid and its products on the face of the case are removed.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. The process of making electroplates,

which comprises treating the face of the case with a solution containing a solvent which dissolves the light oils and foreign matter, said solution also containing a finely divided conducting substance which deposits on the face of the case, and plating thereafter.

2. The process of making electroplates, which comprises washing the face of the case with a solution containing an ink solvent and a finely divided conducting substance which deposits upon the face of the case, rinsing and plating thereafter.

'3. The process of making electroplates, which comprises impressing a waX case with the type, treating said case thereafter with a solution containing a weak acid and graphite, rinsing said case to remove the acid, and plating thereafter.

4. The process of making electroplates,

which comprises treating the face of the case with a solvent, then rinsing thoroughly to remove the solvent and plating thereafter in a bath originally containing approximately the proportions of 1 gallon of w: ter, 23 ounces, 205 grains of copper sulfate 7 and 6 fluid ounces of sulfuric acid.

5. The process of making electroplates, which comprises washing the face of the case with a solution containing a finely divided conducting substance, which will deposit upon the face of the case rinsing said face, and plating thereafter.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

FRANCIS J. MoELHONE. lVitnesses:

F. D. AMMEN,

EVERARD B. MAnsHALL.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. C.