US916033A - Process for producing electrodeposits which can be removed from their base. - Google Patents

Description

H. SGHMIDT. PROCESS FOR PRODUCING BLEOTRODEPOSITS WHICH CAN BE REMOVED FROM THEIR BASE.

APPLICATION FILED AUG.9, 1907.

Patented Mar. 23, 1909.

I x T W/T/VEJJZ'S new and useful Improyement in Processes.

.UN TED STATES PATE T OFFICE.

IRROGESS FOR PRODUCING ELEGTRODEPOSI'IS WHICH CAN BE IIRZE'iMVIElID'FROM THEIR BASE.

Specification of Letters Patent;

Patented March 23, 1909'.

Application filed August 9, 1907.- Serial No. 381,792-

To all whom it may concern:

Be it known that LHARRY SCHMIDT, a sub- %ect of the King of Prussia, residing at O0- ogne-on-the-Rhine, in the Kingdom of Prussla and German Empire, have invented a for Producing Electrodeposits which Can Be Removed From their Base, of which the following is a specification.

1s invention relates to improvements in the roduction of electrometallic deposits, who can be readily removed from their base, (cathode) and'is characterized by anodically catho e and which may be soluble in the partlcular electrolyte) in the electrodepositing bath by an electric current whose electromotlve force is such as not to produce a visible change of the base, whereby there can. be produce by Way of example metal sheets or toll, havmg glossy surfaces without burnishmg, and even of such extreme thinness that burnishing would be impracticable Whereas accordingto the known method preventing adhesion of an" electrodeposit to its base by producing a film of oxitl'on the surface of the base, by reversing the electriccurrent for a very short time, no; particular regard could be had to. the surface polish; Said known method has also the, drawback that the cathode can only be used once without being prepared again, while accordin to the pres ent invention a large number o deposits can be dawn off-the cathode when once prepare If a metal plate anodica-lly polarized as above stated is used as the cathode, an electrodeposit is obtained, whose thickness depends on the strength and duration of the electric current. This cathode, thus provided with a metal coating, can be again anodically polarized and then provided with a new electrodeposit. By repeating this 0 eration any number of times an electro eposit is obtained, which can be divided into its separate layers. If these separate layers are very thin, the whole electrode osit can be ground or crushed to form meta bronze.

The electromotiv'e force employed for the anodicpolarization in order to prevent the deposit from adhering is diflerent accordin to the nature of the metal to be deposite andj; is greater according as the thinner.

deposit is For example, the electromotive force at the screws of the bath in olarizing thebase (which is to serve as.

when producing t ick' electrodeposits is 0.8 volts or less and in roducing nickel foil of the thickness of tin oil is 1.3.volts, while in producing metal de osits which are suitable or being ground to orm bronze about 3 volts are employed. The anodic olarization up to the desired degree is usually obtained in one of two ways, that isz either byusing a current whose electromotive force is 'reater than that necessary for obtaining the desired degree of polarization, in which case, the time during which the current is allowed to act must be very carefully regulated, so that the desired de ree of polarizationis reached and not exceeded; or by using an auxiliary Y which the anodic olarization is carried out,

source of electricity for the anodic polariza-' tion 'whose electromotive force just suflices to produce the desired degree of polarization, in which case, the source of electricity can be switched in for any length of time, without electromotive' force or tension required for any given purpose is 1.5 to 1.6 volts, then a battery consisting of two cells each yielding about 0.8 volts might be used.

Both methods mentioned have advantages and drawbacks According to the first process, it is possible to work qulcker than according to the second process, the operation. however is not so certain in the first case, owing to a nonuniform distribution of the current, which drawback is avoided by the second process.

The invention can also be employed to produce metal foil in an endless strip and ollow bodies as will be evident from the drawings in which I Figure 1 is a diagramniatic view of the cylinder used for producing metal foil in end. less strips. Fig. 2 shows the method of apapplying the templets making hollow bodies, and' Figs. 3 and 4 shoyv two different sta es in makng an endless pipe.

or producing. .metal foil, in an endless strip a rotary cylinder 0. is used as cathode, the current passing from the source I) through the wire 0' to the anodes d and from thence to the cylinder at and through the wire e back to the source b. This current deposits metal on the cylinder, which metal as the cylinder rotates passes through the space f isolated when passing through 9 along the lines coveing ground to form bronze.

from the bath by the partitions g and becomes anodically polarized by a current passing from the battery It through the wire '5 to the cylinder a and I om thenceto the plates k and the wire 1 back to the battery If the deposited metal foil is drawn off the cylinder a at some point m before the isolated art of the bath, an endless strip of metal oil is obtained. If the de osit is left on the cylinder, a strip of metal (ill of any desired length will be s irally de osited on the cylinder. This met o'd can a o be employed for producing extremely thin foil suitable for In this case the speed of rotation of the cylinder must be eater in accordance with the thinness, and

vinstead of the cylinder a disk should preferabg be used. i 2 shows how an endless hollow fpipe may e made. At f the whole len th 0 t e cylinder is anodically polarized,-w 'le at a second isolating space n templets 0 are provided to cover the metal'deposit, along-certain lines where it will not therefore be anodically olarized. As a consequence the metal eposited on the cylinder when passing through, 1) will adhere. to that deposited ered by the templets, while both said deposits will be separate .where the first de posit has been polarized passing through the space n. The endless strip taken off the cylinder at m will therefore have the section shown in Fig. 3. By cutting said strips longitudinally at 1' separate pi es are obtained 1 as shown in Fig. 4. In t is way hollow bodies of various sha es such as bags, for sweetmeats, endless t in pipes, etc., can be made.

What I claim and desire to secure by Letters Patent is n 1. The rocess for producing electrodeposits whic can be removed from their base, which consists in using the base as anode at an electromotive force at which no visible alteration takes place, and in then electrode ositing a metal on said base, substantia ly as set forth. I

2. The rocess for producing electrodeposits whic can be removed from their base, which consists in electrodepositing a metal layer on a rotary cylinder, continuously anodically polarizing said layer and in electrodepositing metal on said first anodically polarlzed layer, substantially as set forth.

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

HARRY SCHMIDT.

Witnesses:

Louis VANDORY, M. KNEPPERS.

Images