Classifications

• • C—CHEMISTRY; METALLURGY
  • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
  • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
  • C25D3/00—Electroplating: Baths therefor
  • C25D3/02—Electroplating: Baths therefor from solutions
  • C25D3/30—Electroplating: Baths therefor from solutions of tin
  • C25D3/32—Electroplating: Baths therefor from solutions of tin characterised by the organic bath constituents used

Definitions

• the invention comprises the features hereinafter fully described, and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative however, of but a few of the various.
• the invention contemplates electro-deposition in an acid type of bath, employing the sulphate, and controlled by an agent which I designate a soluble resin or cresolresin.
• the anode employed may be tin in suitable form, as for instance commercially pure tin, and the cathode may be of any suitable or desired form, depending upon whether a mere coating or a built-up deposit is contemplated.
• the present process allows deposition not only on iron,.steel, copper, and other metals or their I alloys low in the electromotive series, but is also feasibly operative upon zinc, aluminum, and other metals or their alloys high in the electromotive series.
• I incorporate a control agent of a soluble resin character, and desirably of synthetic origininvolving conjugation of phenolic radicles by an organic condensing compound.
• a control agent of a soluble resin character, and desirably of synthetic origininvolving conjugation of phenolic radicles by an organic condensing compound.
• Such an agent may be made for instance by reaction between refined cresol, from which all o-cresol has been removed, and such compounds as an aldehyde as formaldehyde, or gelatin, aloin, etc., and sulphuric acid. While a highly purified form of gelatin may be employed, practically the less purified forms such as glue may be applied.
• I may for example, soften a calculated quantity of glue to a rubbery consistency with the smallest quantity of water, and stir into and heat in an excess of refined ,plete.
• cresol from which the o-cresol has been removed and constituting essentially then a mixture of meta-cresol and para-cresol.
• the mixture is heated to not above C. until reaction is com- Thereupon, a calculated amount of con-. centrated sulphuric acid is added, and the whole is heated to not over 110 C.
• a vdesired amount of gelatin is treated with a calculated quantity of concentrated sulphuric acid, at a temperature not over C. and is allowed to stand'until waste matter rises to the top as scum. This is removed.
• An amount of refined cresol corresponding in quantity to the gelatin is separately treated with an equi-molecular amount of sulphuric acid at a temperature not over C. for a minimum of one-half hour.
• the two solutions are cooled to about 10 C. and are then mixed carefully such that the heat of reaction does not carry the temperature higher than about 60 C.
• the reaction product is a water-soluble material containing little inert matter. If however, the temperature of the reaction were allowed to rise to 80-100 C., the product would be of different and unsuitable character by reason of the secondary reaction occurring.
• tin in relatively great thickness, such as over two thousandths of an inch and more, and the current densities may run as high as 100 amperes per square foot of surface, and the tin is deposited in a dense fine semi-mirror surface such as has not heretofore been possible.
• a fluoride in small amount, such as sodium fluoride, a harder surface results.
• a nickel salt such as nickel sulphate, or nickel fluoride
• the plating bath as preferably used then, may have such a composition as the following, it being understood that the last two ingredients are optionally added for results more desirable for certain usages.
• the solution may be operated at temperatures of 20 C.- C., and current densities of 10-100 amperes per square foot. It correspondingly incurs a low power cost. And unlike prior practice, the plating of tin upon zinc and other like metals and alloys now becomes practicable.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Electrochemistry (AREA)
• Materials Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Electroplating And Plating Baths Therefor (AREA)
• Artificial Filaments (AREA)

Priority Applications (3)

Applications Claiming Priority (1)

Publications (1)

Family

ID=24623478

Family Applications (1)

Country Status (3)

Cited By (5)

Families Citing this family (2)

• 1933
  • 1933-01-28 US US654113A patent/US1987749A/en not_active Expired - Lifetime
  • 1933-05-26 GB GB15248/33A patent/GB404533A/en not_active Expired
  • 1933-05-30 DE DEH136417D patent/DE641107C/de not_active Expired

Also Published As

Similar Documents