US1531140A - Method of forming electrodeposits - Google Patents

Description

- Patented Mar. 24, 1925.

, rectly UNITED STATES I 1,531,140 PATENT OFFICE.

GEORGE SCHNEIDER, OF LA VALE, MARYLAND, ASSIGNO'R TO THE AMERICAN CELLU- LOSE & CHEMICAL MANUFACTURING COMPANY,

LTD, QF YORK, N. Y.

Y METHOD OF FORMING ELECTBODEPOSITS.

Io Drawing; i

To all whom it may concern:

Be it known that I, Gnonon SCHNEIDER, a citizen of the United states residing at La Vale, Cumberland, State of Maryland, have invented certain new and useful Improvements in Methods of Forming Electrodeposits, of which the following is a specification.

This invention electrodepositing a metal upon a prepared object in such manner that it can be easily removed therefrom. The deposit may be of nickel, copper, or other suitable metal or combination of metals, and the object on which the deposit is formed may be of similar material. I

When metal is plated electrolytically diupon an 'object made of the same or another metal or metals, it' is usually very difiicult to separate or strip the plated metal from the object plated. This is particularly the case if an electrodeposit of nickel is made upon a copper object constituting the cathode. I

The object of my invention is to enable a metal, particularly nickel or copper electro plated upon a metal object particularly copper or nickel to be stripped or removed therefrom with great facility or in otherwords, to so conduct the process as to prevent the deposited metal from strongly adhering to the object plated.

In carrying out my invention the object to be plated is prepared by first forming upon the surface thereof an extremely thin electrodeposit which serves as an intermediate layer or lamination. Such thin deposit should have tenacious properties sufficient to allow the final deposit of plate metal to adhere firmly to the object being plated during the plating operation in order to obtain the maximumdefinition of detail effect on the deposit, and also such nonadhering properties as to allow the final deposit to be easily removed or stripped without injuring the surface of the deposit or of the object plated, and thirdly in some cases this thin intermediate layer should be of such character that it will not interfere with the transferrence of the high polish from the surface of the object plated to the de osit or duplicate.

any materials for such an intermediate layer are not suitable for the purposes above mentioned, being either non-adherent or adrelates to a method ofv Application filed January 19, 1924. Serial No. 687,387.

herent to a greater extent than required. Arsenic, electrically deposited, from an appropriate solution is only partially successful for the purposes mentioned because it does not permit the plate metal to adhere sufliciently to the object plated to obtain a deposit of the desired thickness, inasmuch as it is under electrical tension while being formed and would separate from the object before completion.

I have discovered that if this very thin deposit or intermediate layer be formed of an admixture of nickel, copper or other suitable metal or metals and arsenic in .the proper proportions, -the desired results are satisfactorily obtained. By employing for this layer the substances just mentioned, the desired final deposit can be made of'the required thickness for use and it will adhere firmly to the object treated While being deposited and when the deposition is completed the final deposit can be easily stripped from said plated, object.

When nickel and arsenic are used the desired proportions of these may be defined or ascertained by the color of the deposit, which latter is extremely thin, being only a fraction of a thousandth of an inch in thickness and the color appears as a mere blush or flash upon the polished surface of the object and should, I have found, be of a steel blue tint.

While arsenic deposits as dead grayish black and nickel as bright white, the two when combined in proportions, as above described, produce a deposit of the steel blue color above mentioned and the polish of the treated object is retained. The treated object after being flashed with the materials above mentioned may be plated in a suitable electroplating bath of copper, nickel, or other desired metal and a deposit of the desired thickness of metal is thus obtained. When the last named'deposit has reached the desired thickness, the plated object may be-Withdrawn from the bath and the electroplated deposit may be readily stripped or removed. The intermediate thin layer is more or less absorbed by the final deposit and in no way detracts from the exact duplication produced in the stripped deposit of any of the detail effect present on the surface of the object plated.

In this way metals of many kinds may be deposited singly or in combination as a laminated sheet or as a mixed deposit and readily stripped from an object made of the same or other metal or metals.

In some cases instead of forming the intermediate layer of nickel and arsenic, other suitable metal may be used in place of to one of the mtal'used.

When practicing the process for the making of nickel deposits I preferably proceedas follows though the scope of my rocess is in no way confined to thisparticu ar example. The object .to be treated is used as a cathode and may be of copper or other suitable metal or metals. It is first ohshe d and either with or without a nicke face 13 placed in a bath consisting of an admixture of the usual nickel'plating salts and wh te arsenic and/or sodium or potassium arsemte in the correct pro ortions. For example a plating bath suita Is for the purpose would consist of:

'13 parts nickel'ammonium sulphate,

4 parts zinc sulphate,

4 parts sodium chloride,

5 parts ammonium carbonate,

8 parts sodium cyanide,

1 part sodium blsulphite,

20 arts arsenite (9 parts AS203, 10% parts aOH).

-The plating operation 1s conducted for a very brief period and at a low current density and tension. A plating period of two minutes at a temperature of 30 C. and a current density of to ampere er sq. decimeter at four to five volts has been found to give the desired flash. The cathode is then washed and without drying is laced in a nickel platin bath and treate in the usual manner well own in the art until the desired thickness of deposit is obtained. As soon as such thickness is obtained, the plated object 1s removed from the bath and the deposit is stripped or removed from the object and 1s ready for use. The cathode or chest may be again prepared and plated 1n the manner before descrlbed.

My invention may be used in the manufacture of various articles, such as talk ng machine records, printing plates, etc. When making talking machine records, the member, known in the art as the mother, 1s" according to m invention treated in the manner before escribed to produce by electrodeposition on its surface a thin layer i. e. a flash or film of arsenic and nickel. This deposited material serves as an intermediate non-adherent or anti-adherent film and on this film I deposit a sufiicient amount of nickel to produce the desired nickel shell to be used in the manufacture of records. For economic reasons this shell is often given a subsequent treatment in a copper lating bath until of the desired thickness.

he character of the intermediate layer or film, which is of very minute thickness, must be such that the subsequent depositing of the pure nickel thereon can be carried to completion without separating or strip ping under electrical tension from the mot ier member on which it is deposited. The film should also have such non-adherent properties as to enable the final deposit of nickel to be readily separated when completed. One of the features of my invention, therefore, is its adaptability to the manufacture of talking machine records from shells made of nickel which are capable of producing records of superior qual- I .ity over those. made from copper or nickel faced copper shells and, furthermore, it'will be observed that in the manufacture of such I nickel shells I am able to strip the nickel shells from the mother or foundation on which they are formed with great facility without in any way injuring either the record forming surface or the surface of the mother.

I claim as my invention:

1. The method hereinbefore described of forming a metal deposit upon an object to be plated, which consists in first formin on the surface of the object an intermediate deposit of a mixture of arsenic and one of l the heavy metals, and then depositing a plating metal on such treated object until a plating of the desired thickness is obtained.

2. The method hereinbefore described of forming a metal deposit upon an object to be plated, which consists in first forming on the surface of the object a deposit of a mixture of one part nickel and three to four parts arsenic and metal on the treated obiect until a plating of the desired thickness is obtained.

3. The method hereinbefore described of forming metallic negatives of an object, which consists in first flashing or thinly plating the object with a mixture of arsenic then depositing a plating desired thickness is obtained, which may be removed.

5. The hereinbefore described method of forming a metallic shell for the manufacture of talking machine records, which consists in forming on a metal surfaced member or mother a thin film or flash of an electrodeposited mixture -of arsenic and one of the heavy metals, and then electrodepositing a plating metal on said treated member or mother until a shell of the desired thickness is obtained which may be removed.

6. The hereinbefore described method of forming a nickel shell for the manufacture of talking machine records, which consists in forming on a metal surfaced member or mother a thin film or flash of electrodeposited nickel and arsenic, and then electrodepositing nickel on said treated member until a nickel shell of the desired thickness is obtained which may be removed.

7. The hereinbefore described method of forming metallic shells for the manufacture of talking machine records, which consists in forming on a metal surfaced member a thin film or flash of an electro deposited mixture of arsenic and one of the heavy metals, then eleetrodepositing a plating metal on said treated member until a shell of the desired thickness is obtained and then stripping or removing the shell from said member.

8. The hereinbefore described method of forming a nickel shell for the manufacture of talking machine records, which consists in forming on a metal surfaced member or mother a thin film or flash of electrodeposited nickel and arsenic, then electrodepositing nickel on said treated member until a shell of the desired thickness is obtained and then stripping or removing the nickel shell from said member.

In testimony whereof, I have hereunto subscribed my name.

GEORGE SCHNEIDER.