Tin plating

Uses of hydrogen chloride—Hydrogen chloride is sometimes used in the preparation of an ester, for example ethyl benzoate, where it acts as both an acid catalyst and a dehydrating agent. Hydrochloric acid is used primarily to produce chlorides, for example ammonium chloride. It is extensively used in the manufacture of anilme dyes, and for cleaning iron before galvanising and tin-plating. 

Containers. Aerosol containers, made to withstand a certain amount of pressure, vary in both size and materials of constmction. They are manufactured from tin-plated steel, aluminum, and glass. The most popular aerosol container is the three-piece tin-plated steel container. Glass containers, which are usually plastic coated, generally have thicker walls than conventional glass jars. They are limited to a maximum size of 120 mL and are used for pharmaceutical and cosmetic aerosols. 

In order to increase resistance of the container to the effect of the product or to protect the product from the tin plating, an inert, internal organic coating can be appHed. 

The mounting cup (ferrule for botde valves) mechanically joins the valve to the container. The mounting cup may be made from a variety of materials, but is typically tin-plated steel coated on the underside. It contains the gasket which provides the seal. Soft gasketing material is appHed wet and bonded in place or, more frequently in larger cans, cut mbber, polyethylene, or polypropylene gaskets are used. 

Sepro Conta.iner, The Sepro container consists of a collapsible plastic bag fitted into a standard three-piece, tin-plated container such as a 202 X 214, 202 x 406, or 202 x 509 can. The product is placed within the bag, and the propellant is added through the bottom of the container, which is fitted with a one-way valve. There is no limitation on the viscosity of the product but compatibiUty with the plastic bag must be considered. A free-dowing hquid can be dispensed either as a stream or a fine spray, depending on the type of valve employed. A viscous material is often dispensed as a stream. This system has been used for caulking compounds, postfoaming gels, and depilatories. 

Three-Piece Cans. Most steel cans, whether or not tin-plated, are three-piece, ie, a body and two ends. In the past, solder was used to bond the longitudinal seam, but solder has been replaced by welded side seams. 

The composition of the builders in an alkaline cleaner is dependent on the metal substrate from which the soil is to be removed. For steel (qv) or stainless steel aggressive, ie, high pH, alkaline salts such as sodium or potassium hydroxide can be used as the main alkaline builder. For aluminum, zinc, brass, or tin plate, less aggressive (lower pH) builders such as sodium or potassium siUcates, mono- and diphosphates, borates, and bicarbonates are used. 

Copper is universally used as the metal plating for tape because it can be easily laminated with copper and the various plastic tapes. Copper is readily etched and has excellent electrical and thermal conductivity in both electrodeposited and roUed-annealed form. The tape metal plating is normally gold- or tin-plated to ensure good bondabiUty during inner- and outer-lead bonding operations and to provide better shelf life and corrosion resistance. 

Ammonium chloride has a number of iadustrial uses, most importantiy ia the manufacture of dry-ceU batteries, where it serves as an electrolyte. It is also used to make quarryiag explosives, as a hardener for formaldehyde-based adhesives, as a flame suppressant, and ia etching solutions ia the manufacture of ptinted circuit boards. Other appHcations iaclude use as a component of fluxes ia ziac and tin plating, and for electrolytic refining of ziac. 

A reversal of potential of the tin—iron couple occurs when tin-coated steel (tin-plate) is in contact with acid solutions in the absence of air. The tin coating acts as an anode it is the tin that is slowly attacked and not the steel. This unique property is the keystone of the canning industry because dissolved iron affects the flavor and appearance of the product. Thus, the presence of tin protects the appearance and flavor of the product. 

Hydrated Stannic Oxide. Hydrated stannic oxide of variable water content is obtained by the hydrolysis of stannates. Acidification of a sodium stannate solution precipitates the hydrate as a flocculent white mass. The colloidal solution, which is obtained by washing the mass free of water-soluble ions and peptization with potassium hydroxide, is stable below 50°C and forms the basis for the patented Tin Sol process for replenishing tin in staimate tin-plating baths. A similar type of solution (Staimasol A and B) is prepared by the direct electrolysis of concentrated potassium staimate solutions (26). 

Potassium staimate, K2Sn(OH) (mol wt 298.93), and sodium stannate [12058-66-17, Na2Sn(OH), mol wt 266.71, are colorless crystals and are soluble in water. The solubiUty of potassium stannate in water is 110.5 g/100 mL water at 15°C and that of sodium stannate is 61.5 g/100 mL water at 15°C. The solubihty of sodium stannate decreases with increasing temperature, whereas the solubiUty of potassium stannate increases with increasing temperature. The solubihty of either sodium or potassium stannate decreases as the concentration of the respective free caustic increases. Hydrolysis of stannates yields hydrated stannic oxides and is the basis of the Tin Sol solution, which is used to replenish tin in stannate tin-plating baths (28,29). 

Fretting corrosion (36,37) can lead to high contact resistance of base metal contacts, such as tin plate in electronic connectors. Small cycHcal displacements of the connector halves occur because of external vibration or differential thermal expansion and contraction of the mating contacts. The wear debris that is formed remains in the contact zone. The accumulation of oxide debris in the contact region leads to increased contact resistance. Solutions to this problem are stmctures that do not permit movement of contact surfaces with respect to one another, the use of gold as a contact finish, and the appHcation of thick coatings of contact lubricants and greases, which reduce the rate of wear and restrict access of air to the contact surfaces. 

Tin. Apphcation of tin on strip steel for can stock has decreased. Nevertheless, tin plating is still done in large volume, and tin plate for can stock was estimated at 11,750 t in 1990 (11). Additionally, 603 t of tin anodes were used for electroplating in electronic apphcations in the United States in 1990. The use of tin in solder manufacture is reported to exceed that used in can stock (12). The cost of tin in early 1993 was 7.50/kg (see Tin and tin alloys). 

Special containers have been developed for anesthetic ether to prevent deterioration before use. Their effectiveness as stabHizers usuaHy depends on the presence of a lower oxide of a metal having more than one oxidation state. Thus the sides and the bottoms of tin-plate containers are electroplated with copper, which contains a smaH amount of cuprous oxide. Staimous oxide is also used in the linings for tin containers. Instead of using special containers, iron wire or certain other metals and aHoys or organic compounds have been added to ether to stabHize it. 

Apart from its structural interest, SnCl2 is important as a widely used mild reducing agent in acid solution. The dihydrate is commercially available for use in electrolytic tin-plating baths, as a sensitizer in silvering mirrors and in the plating of plastics, and as a perfume stabilizer in toilet soaps. The anhydrous material can be obtained either by dehydration using acetic... 

Blech, n. plate, sheet, sheet metal, specif, slieet iron foil (weisses) tin plate (schwarzes) black iron plate, -aussetmitt, -ausstoss, m (Metal.) blank, -biichse, /. tin can, tin. -dose, /. tin box tin can, tin. -eisen, n. sheet iron. 

Blech flasche, /. narrow-necked tin vessel, -ge-fass, n. tin (plate) vessel, -gluhofen, m. plate-heating furnace, -hsfen, m. tin can. 

Blech-konne, /. tin can. -kasten, m. tin box sheet-iron box. -lack, m. tinplate varnish sheet-metal varnish, -messing, n. sheet brass, -rohr, n. sheet-iron tube tin tube, -schmied, m. tinner, -stfirke, /. plate (or sheet) thickness, -taiel, /. sheet iron, iron plate. -trichter, m. tin (plate) funnel, -trommel, /. tin (plate) drum, -ware, /. sheet-metal ware, ( i ually) tinware. 

Saum, m. seam, hem, edge, fringe, selvage border, margin (Tin Plate) list. 

Saum-pfanne,/. (Tin Plate) list pot. -riff, n. fringing rerf. -spiegel, m. gray apiegeleiaen. -topf, m. — Saumpfanne. 

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