DE2907233A1 - TIN SHEET CONTAINER AND METHOD FOR THE PRODUCTION THEREOF - Google Patents

Description

PATENT LAWYERS

A. GRÜNECKER H. KINKEUDEY

DR-INd

W, STOCKMAIR

DR-ING-AeElCAlTECH)

K. SCHUMANN

DR RER ΝΑΓ - OPL-FHYS

P. H. JAKOB

DIFLlNG.

G. BEZOUD

□ R RER NAT - OtPL-CHEM

8 MUNICH

IUlAXIMtUANSTRASSE

P 13 557

THE BEOSEF HILL PROPEIITAET COMP. LTD,
Melbourne, Victoria (Australia)

Tinplate containers and process for their manufacture

The invention relates to the manufacture of tinplate and tinplate containers, in particular cylindrical ones Tinplate cans with soldered longitudinal seams.

Tinplate for cans is generally made by electrolytic deposition of tin on! thin sheet made. In the case of electrolytic tinning, a Steel strip successively electrolytically cleaned »lightly pickled, electrolytically tinned, a remelting treatment for the deposited tin and subjected to a final chemical or electrochemical Subjected to passivation treatment. Also called "flow-" brightening " designated remelting process includes

230723

a melting of the deposited tin layer by Conduction, radiation or high frequency induction heating to a temperature slightly above the melting point of Tin lying temperature, so that the tin becomes molten and produces a smooth shiny surface, whereby In addition, a proportion of the tin and the steel of the sheet metal substrate form an alloy. layer connects.

There are basically three electrolytic tinning processes, which differ from one another mainly through the different electrolytes. the electrolyte is contained in vertical sections and becomes the steel strip material Alkali or "stannate lines", which run down between the tin anode banks, essentially agree correspond to the aforementioned systems, but use one alkaline sodium stannate electrolytes.

The third electrolytic tinning process is known as the "halogen process". In systems of this type a halogen electrolyte arranged in a multitude of small cells, each with its own circulation system, contact rollers and anode banks. The steel strip material is placed horizontally across the top surface of the electrolyte in a multitude of cells out so that the strip material is tinned only on the underside. The tape material is then after guided up and back, so that the previously upward facing surface becomes the underside. The steel band material is in this arrangement by a multitude

909835/0807

further electrolytic cells led, so that too the other upper side of the strip material receives a tin coating. Working with halogen electrolytes Systems can work with high belt throughput speeds and also have the advantage that Coatings with different weights on the Tape can be applied, meaning coatings of different thicknesses on the two Sides of the coated sheet can be provided.

Modern high-speed systems for tin can production confront tinplate manufacturers with increased quality requirements. This applies in particular to the production of cans with soldered seams _9, since in the high-speed production of cans, poor solderability of the tinplate can lead to major operational disruptions.

At present, tinplate cans with longitudinal seams are generally made from re-melted (flow-brightened)

Tinplate with a coating of at least 2.5 g / m 2 manufactured. Such a coating thickness is considered to be necessary for adequate corrosion resistance and to ensure good solderability. The invention is based on the fact that it has been found that a thinly tinned and not remelted tinplate after production under adequately controlled conditions can certainly have properties which one Glossy white sheet metal with a considerably thicker tin coating are comparable. As a result, a more cost-effective material can be used for the production of cans, while at the same time solving the problem of solderability in high-speed systems is fed.

909835/0807

According to the invention, a method for producing a container with a tubular tinplate wall and an external soldered longitudinal seam is proposed, the wall consisting of an electrolytically produced and not remelted tinplate, which on its outer side of the tubular wall defines a thin tin coating with a Coating weight of less ats 2 g / m _r preferably

ο
from 0.5 to 1.5 g / m 2.

The tinplate can be produced on both sides with essentially similar tin coatings or, alternatively, also in this way that the tin layer on one side of the tinplate is thicker than on the other side.

The invention also provides a container with a cylindrical Tinplate wall, which has a longitudinal seam soldered from the outside, the tinplate of this container wall a non-remelted electrolytically manufactured tinplate with an outer layer of tin

2 with a coating weight of less than 2 g / m and is preferably in the range from 0.5 to 1.5 g / ω.

During the preparation of a suitable thin-coated Tinplate using the halogen process has been found to be of the utmost importance Excretion of hydrated tin compounds on the tin coatings in the treatment sections to a large extent to prevent. This can be achieved by having a high concentration of fluoride ions in the cleaning agent (rinsing agent) is maintained and that also the ratio of fluoride ions to tin (II) ions in the Cleaning section is held abnormally high.

909835/0807

• J.

The invention thus also comprises a method for producing electrolytically with the aid of the halogen method manufactured tinplate. This process involves the electrolytic application of tin coatings on the opposite surfaces of a steel strip material, being a tin (II) ion and electrolyte containing fluoride ions is used, and the cleaning or rinsing of the coated strip material in a cleaning or rinsing agent containing fluoride ions, which because of the drag-in of Electrolyte through the coated sheet metal also tin (II) ions may contain. The tin coating is electrolytically applied to at least one of the two surfaces of the Steel sheet material applied, the coating

is applied with a layer weight of less than 2.5 g / a and a ratio of fluoride ions to tin (II) ions (F ~: Sn ⁺⁺ ) of less than 10: 1 is maintained in the cleaning or rinsing agent.

The concentration of fluoride ions in the cleaning or rinsing agent is preferably not less than 8 g / l, with a concentration of 10 to 20 g / l being very particularly is preferred.

The ratio of fluoride ions. to tin (II) ions (F ~; Sn ⁺⁺ ) in the electrolyte can be in the range from 8: 1 to 15: 1.

The electrolyte can consist of tin (II) ions, chloride ions * fluoride ions, iron (II) cyanide and a brightener. The cleaning or rinsing agent can consist of an aqueous solution of sodium bifluoride and / or sodium fluoride. A one-sided coating with a coating weight of 0.5 "to 1.5 g / m is preferably applied electrolytically»

909835 / -

It has also been found that the precipitation of hydrated tin compounds can affect the tin coatings can be reduced most effectively during the cleaning or rinsing process, if the in the detergent or cleaning agent the fluoride ions contained are in a suitable form to form complexes with tin, but this only takes place in an acidic environment. In particular, it was found that the pH of the detergent should preferably be kept below 4 x, for example by adding a suitable hydrochloric acid - commercially available concentrated hydrochloric acid proved to be suitable for this purpose. The invention also encompasses that by means of the foregoing Process produced electrolytically produced and. tinplate not melted again.

Further features, advantages and details of the invention emerge from the following description with reference to FIG Drawing. In this shows:

Fig. 1 is a schematic representation of a horizontally arranged el ect ro Iy ti see tinning plant for tinning with a halogen electrolyte,

Figure 2 is a perspective view of a typical with portions broken away Food can with double-hemmed ends and secured and soldered side seam,

3 shows a cross section through the side seam of the in Fig. 2 can shown,

Fig. 4 is a cross section through one of the end seams of the Food can,

909835/0807

ψ-

I? Ig »5 a micro profile of an electrolytically manufactured Tin coating on a sheet steel substrate,

Fig. 6

and Fig. 7 explains the operation of remelting or "flow-brightening" of the coating,

8 shows an illustration of the structure resulting from remelting and FIG

Fig. 9

through 14 graphs showing the results of on samples from remelted and not remelted tinplate with different coating thicknesses YersuGhe pose.

The schematic in Pig. 1 illustrated electrolytic tinning plant according to the halogen process comprises two decoilers 11 for unwinding Peinblech coils. This allows switching from one decoiler to the other. The sheet metal strip 12 is fed from the respective decoiler through a loop device 13 * which serves as ffeterial supply, to a high-speed pulling device 14 and through an alkaline electrolytic cleaning bath 15, a rinsing device 16, an auxiliary 1? and a further flushing device 18 to the electrical tin-plating device, which is generally designated by the reference numeral 19 "The torrent loop device 13 serves to collect tape material, so that the collected material can be dispensed as an isontinuous tape when the front filament of a subsequent coil to the tail end of the νοτ— going coil in a viewing and welding station

909 8 35/0807

290723

is welded on.

Arrives in the electrolytic tinning device 19 the steel belt through a multitude of electrolytic cells 21, each with its own circulation system, have their own contact roller and tin anode bank. The containers are designed in such a way that that the strip material is only immersed in the electrolyte and only tinned on the underside. That Strip material is then passed up and back over a further plurality of electrolytic cells 22, so that the initial top is now tinned as the bottom.

After leaving the electrolytic tinning facility, the double-sided tinned sheet is passed through a rinsing container 23 and a passivation container (not shown) guided.

The material can also be fed through an oil coating device and a further loop memory or the like a not shown Aufhaspe! device out will.

The electrolyte contained in the electrolytic cells 21 typically has the following compositions:

Tin (II) ions (Sn ⁺⁺ ) 12 to 25 g / l

Chloride ions (Cl ") 38 g / l

Fluoride ions (J ") 34 g / l

Ferro-cyanide 0.75 g / l

Rinse aid 3.5 g / l

909835/0807

Under operating conditions, the ratio of fluoride ions to tin (II) ions (F ~: Sn ⁺⁺ ) in the electrolyte is within a range from 8: 1 to

The detergent contained in the container 23 can be demineralized Contains water and dissolved sodium bifluoride (NaHFp) or sodium fluoride (NaF) - sub Operating conditions, the detergent also contains a proportion of both tin (II) and tin (IV) - "chloride and fluoride ions, which are brought in from the electrolyte with the steel strip. Appropriate devices are provided to recover the electrolyte from the wash tank and to feed it back to the electrolytic cells of the tinning facility »

The halogen tinning plant shown is complete conventional and details of the electrical cells and auxiliary equipment are known to those skilled in the art.

2 shows a typical tinplate can 24 with a tubular side wall 25 and ends 26 _? 27 »The cylindrical side wall has a flanged and soldered longitudinal seam 28, while the two end covers are connected to the tubular wall with the help of double flanged seams 29» The formation of these side faces 28 is shown in FIG Fig. 4 is shown-,

The in the - ^ ig. Bosenkonstruktion illustrated to 3 2 is entirely conventional and enables Doseilherstellung on modern high-speed machines sma ^ In such machines are blanks or blanks for the Seitem-jandungen fed to a can manufacturer, who zn sylinderförmigen structures having a longitudinal seam 28

processed. The cylindrical bodies then go through a high-speed sieving machine, soft along the A plumbing 31 brings down the outside of the flanged seam 28 (Fig. 3). The crimped and soldered can bodies then go to a flanging machine, which each Can end provided with an outwardly turned splash. The flanged can bodies are then brought to a double seam builder, which connects one of the end flanges to the body and thereby a Double flare forms to connect the end of the body to the flange. A seal is generally used arranged before the double flanged seam is formed. Usually the can produced becomes the next Processing station with open top fed and this top side or the can lid is at the end of the can production process by means of a double flanged seam connected to the can body.

Usually the inside of the can is covered with a protective coating from a lacquer or the like. Provided, this lacquer on one side before the manufacture of the can of the tinplate is applied.

The machine equipment for the production of cans has not been described in detail above, but is known to the person skilled in the art. The invention is primarily concerned with the tinplate, as it is for such Machine equipment is used

If tin is electrolytically applied to a steel substrate in the halogen process, the theory predicts that with the respective degree of roughness of the steel substrate (0.2 to 1.0 µm; CLA 25 to 150 peaks / cm) the current distribution on the micro profile of the steel substrate is such,

903835/0807

that the tin deposition parallel to the contours of the steel substrate follows. This effect is shown in Fig. 5, in which the tin coating with the reference number 31 and the steel substrate with the reference number 32 are designated.

Microscopic, non-metallic particles that are always found on the steel surface will be bridged by tin during Terzinnens, provided they are not too big or wide. This "bridging effect is shown in Fig. 6, which is one of a passivation film 33 covered tin plating 3Ί and a non-metallic Particle 3 ^ - represents, the latter being from the tin coating has been bridged leaving a narrow gap.

During remelting or "flow-brightening", which is done with conventional production methods to give the tinplate the pleasant shine, the The flatness of the tin coating is lost and the tin flows into the irregularities under the influence of surface tension of the steel substrate and the grinding channels (temper grind channels) in order to form small pores, as indicated in FIG. 7.

Some of the tin combines with the steel substrate to form an alloy. This effect is in Fig. 8, where it can be seen that the overall effect of remelting is that a very uneven coating occurs and the so-called peaks have less coating material. In some cases these peaks are even only "covered" by alloyed tin *

The non-wettability (dewetting) of non-metallic see Surface depends on the ratio of the tin thickness to the width of the

309835/0807

Final and the surface tension of the tin. Thin Tin coatings such as those labeled EO 5 "with

2.8 g / m coating weight favor the extreme wettability, but if the coating thickness is reduced still further, the film wettability is still lower stronger. The unwetted areas of the steel substrate and the associated pores are covered with chromium compounds during the chemical passivation process of the tinplate 'Clogged', so to speak, and during the soldering process these surfaces work together with some alloying agents. stratified peaks as barriers which prevent the flow of the solder hinder. Thus, tin plates are with coating weights of less than E05 has heretofore been considered unsuitable for canning.

If the electrolytically deposited tin is not melted again, those bridged by tin remain hidden non-metallic inclusions, which reduces the number of solder locks and accordingly improves solderability.

The increase in porosity (number of pores) that occurs when decreasing of the coating weight was observed is shown in Fig. 9 and it is found not again molten tinplate is superior to remelted tinplate in this respect.

Fig. ΊΟ shows the results of the so-called. ISV test .Clon Solution Value) based on samples from non-melted and molten material of different coating weights had been carried out. The ACTUAL attempt is used to determine the amount of non-wetted steel and it can be seen that by remelting there is an increase in the non-wetted steel surfaces. Will If the tin coating weight is reduced, then there is an increased amount of non-wetted steel

9 0 9835/0807

the covering capacity of the tin that has not been remelted is clearly better.

The direct consequences of the experimental results discussed above can be summarized as follows will:

i) The extent to which the tin is coated on the steel substrate is the main affecting solderability. factor.

ii) The solderability is therefore independent of the tin coating weight. The influence of increasing coating weights must reduce the non-wettability to some extent MaSe overcome and thus indirectly improve solderability.

iii) The remelting of electrolytically deposited Tin layers lead to non-wetted! "Laugh of the Steel substrate through the tin and to a flow of the controlled by the surface tension of the Tin from the peaks, which improves solderability.

During reflow, some surface areas of the steel substrate are not covered (wetted) by the molten tin. This is labeled ^"r Hichtbenetzbarkeit gemeint.Die sequence are not covered with tin surfaces of the steel substrate (iron exposure).

It can therefore be expected that one will not return Melted tinplate with a thin coating has properties that are similar to those of glossy white sheet are comparable, which has higher coating weights. In particular, it can be expected that Satisfactory solderability in the case of such a tinplate that has not been remelted with a thin tin coating can achieve.

To confirm the test results discussed above and predictions x-rarde not re-melted

909835/0807

- 14 / -

Material produced with tin coating weights from 3 »36 to 0.56 g / m ² (E06 to EO1) in steps of about 0.56 g / m ² and examined for solderability and corrosion resistance. 11 to 14 show the test results together with comparative tests carried out on re-melted material.

As can be seen from Mg. 11, the soldering behavior is satisfactory if the material is not remelted with a coating weight of only 0.5 g / m (E01 corresponds to 0.56 g / m), whereas the

2 remelted comparison tinplate over 2.0 g / m 2 more tin is required to achieve comparable soldering properties to show.

The phenomenon of devretting, which has been discussed above, not only serves to influence the soldering behavior, but the extent of non-wetted areas of the steel substrate also governs the resistance of the tinplate to external corrosion. In FIGS. 2 to 2, the corrosion behavior of re-melted and non-re-melted material are compared with each other, with different corrosion resistance tests being carried out. The test results show that over the range of the tin coating weights considered, the material that has not been remelted is clearly superior to the remelted material. The corrosion tests show that the corrosion resistance of the unmelted E02 material (1.1 g / m ² ) can be equated with that of the E04 (2.2 g / m 2) to E05 (2.8 g / m ² ) again melted material.

The above test results were obtained on tinplate, which was put on a Halbgen machine, such as

909835/0807

^29O7Z33

in Fig. 1, and it has been found that it can be used for the manufacture of light coat weight Tinplate with improved soldering behavior is of particular importance, a high fluoride material to be maintained in the rinsing container 23 «Because if the tinplate is not melted again, the properties which are present in the material after electroplating, special attention must be paid to rinsing can be given as a gift in order to avoid the precipitation of hy & ratized tin compounds on the tin coating. It has been found that poor solderability occurs, if the ratio of fluoridones to tin (II) ions im The rinsing tank sank to below 10: 1. It was also found that poor soldering behavior occurs when when the lluoride concentration in the detergent is below of about 8 g / l, the best results were achieved when the fluoride concentration in the detergent was between 10 and 20 g / l.

Thorough investigations have also shown that solubility impairments by the deposition of Tin compounds on the tin coatings during rinsing can be avoided most effectively if they are in the detergent contained fluoride ions in one for complex formation present capable of tin, this only occurs in an acidic environment. So became through the Experiments found that best results are obtained when the pH of the detergent is below of 4 lies. This can be easily done by adding appropriate amounts of commercially available concentrated Reach hydrochloric acid.

It is believed that the surprisingly good solderability and corrosion resistance of the invention

909835 / 0-8 07

, _fi0 , 2307233

Unmelted and thinly coated material is due to the superior coverage of the steel substrate, the uniform thickness of the tin coating on the contours of the steel substrate, and the low level of surface impurities in the tin coating- TJm this was to check commercial amounts of unmelted tinplate with a coating weight of 0.95 g / ^m and this material showed the behavior in laboratory tests and in trial use in high-speed can manufacturing plants. In a trial can production, 3 tons of this material were divided into 800 χ 858 mm and the blanks produced were divided into two parts, which were sent through conventional high-speed can-making equipment. On the first part of the blanks, cans for beverages were successfully produced. The painting, both inside and with a multitude of jars ^ for ^ external decration and - soldering, made T ^ ch ~ ^ very successful. "Firing the lacquers required the greatest expenditure of time and temperature, and led to half of the available tin going into alloy - This means that the free tin content before soldering was 0.5 g / m, was meaning only 20% of the otherwise ^ usually found in E05-quality free Sn, and ö ^ CSS _^% d_och a satisfactory solderability existed. While × e ~ "se ~ s ~ Ver · = ^ Suches was noted that the scrap (fabrication damage) was not greater than with the E05 material and that the use of opaque paintwork meant that the E02 cans could hardly be distinguished from the E05 cans.

The second part of the blanks was also used for production used by beverage cans and in turn showed

909835/0807

• Sri °

that the paintability is very good and was the same or even better than the

Bre-experimental doses prepared were subjected to the so-called 'shelf life test, and it was found that substantially no difference exists between the ~ Shelf i ± f e-results of ^ Q2 Mattdosea and conventional produced from remelted EO $ ~ materials Cans *

After these two successful attempts at can production, some 35 production test runs were carried out, whereby - at least the "production of 3 tons of tinplate (with low coating weight and not melted again) had to be made. sge'saiat some ^^ OQ, ^ material were produced and processed «, ~ Ettfa ~ 5 ^ OOO_ S-oserrTür M'Bx ^ üSd ^ GStSäsk ^^ were made in addition to about 52,000 food cans ^ with the last ones both the-Sosenköf ^ ei ⁵ 'as well as "" can ends! "or. -boden off. The njLcfefe ~ 1ra.ed.er fused material passed ^ All these cans successfully withstood a shelf life trial of at least three months. In a few d ^ gpa ^ -ire ^ zth test runs. wg ^ d & Sr ^ il tins soldered with pure tin solder are traditionally more difficult to use and lead to a higher proportion of soldering in conventionally manufactured tinplate products than when using normal lead-tin solders, "The usual minimum coating weight for low-melted products for pure tin solders corresponds to E05" and most can manufacturers use tin solder - ¥ ea? Use a quality corresponding to at least E07 »Bas according to the invention, manufactured, not remelted material

909835/0807

with a coating weight corresponding to EO2 however, it is always satisfactory in a conventional one Can making arilage with pure tin solder: solder.

The trial manufacturing processes have also shown that it is important to carefully adjust the current density in the electrolyte cells in order to obtain a product of consistent quality. The current densities should be between 600 and 1600 A / m and particularly preferably between 700 and 1200 A / m. In certain tinning-types are for a D _{ur> e} hsatzgeschwindigkeit of 550 m per minute of sheet steel only 6 to 12 cells required within the most preferred current density range. Conventional remelted EO2 sheet metal requires a current density of typically -1500 A / m ² in a 16-cell system.

From the foregoing it will be seen that the invention permits the manufacture of tinplate with a 66% reduced coating weight which is suitable for high speed can manufacture while overcoming the soldering performance difficulties commonly encountered in conventional can manufacture with heavier coating weights. The material according to the invention can be produced on existing electrolytic tinning plants without changing the mechanical or electrical conditions and leads to an energy saving of about 60 %.

909835/0807

The test runs discussed above are merely exemplary in nature and it is understood that the Invention is not limited to the materials used in the trial runs «. It goes without saying " that the invention encompasses a range of tinplate, that have low coating weights and are not melted again Coating weights on the two sheets Sides are commonly used for making painted cans. In the case of unpainted cans, As those are used for some fruits and fruit juices «, it is possible to use different coating weights to use on the two sheet metal surfaces »to give a thick tin coating in this way, for example on the inside of the can and a thin tin coating on the outside of the can, all the more so is the solderability and corrosion resistance according to the invention ~ £ ehiie ^ to achieve.

Although the longitudinal seam is more typical and shown in FIG. 2

up to 4 of the cans shown as a flanged seam ^ dexHdergl ^,

is carried out, the thinly coated and not remelted tinplate according to the invention can also be used for overlap seams, which used for cans containing non-corrosive or non-pressurized contents should.

It is also possible to use cans according to the invention from appropriately thinly coated and not again to produce melted tinplate, the mil; processes other than the halogen process have been. It goes without saying that the person skilled in the art can still make some modifications within the inventive concept is possible.

909 83 5/0807

Claims (1)

PATENT LAWYERS THE BEOKEN HILL PROPRIETARY COMP. LTD, a. srOnecker DlPU-IPiG H. KINKELDEY OR-UMG W. STOCKMAIR CM-ING AeE (CALTECHl K. SCHUMANN DH. RER NAT DIPL PHYS P. H. JAKOB DfPL-IPJG Θ. BEZOLD Dft RER ΝΑΕ * DtPt- -OffiPA 8 MUNICH MAXIMILIANSTRASSE P 13 Claims / Iy method of making a container with a tubular tinplate wall, on which a longitudinal seam soldered from the outside is formed, thereby characterized in that the wall consists of an electrolytically produced and not remelted Tinplate is made, which on its the outside of the tubular wall defining Make a tin coating with a coating weight of less than 2 g / m 2. 2. The method according to .Anspruch 1, characterized in that the coating weight is in the range of 0.5 to 1.5 g / m ² » 5. The method according to claim 1 or 2 _%, characterized in that the container at each end of the tubular wall by means of an end wall in the form of a disk made of an electrolytically produced and not remelted tinplate. month TEt COPIER is closed, with the tinplate on its the Outside of the surface defining the end wall a tin coating with a coating weight of less than 2 g / m 2. 4. Container with a tubular tinplate wall in which a longitudinal seam soldered from the outside is formed is, characterized in that the tinplate of the wall is made of electrolytically produced and not remelted tinplate, which has an outer tin coating with a coating weight of less than 2 g / m 2. 5- container according to claim 4-, characterized in that the coating weight in Range from 0.5 to 1.5 g / m 2. 6. Container according to claim 4- or 5, characterized in that two end walls in Form of disks are connected to the ends of the tubular wall by flanged seams and that each Electrolytically produced and not remelted tinplate end wall an outer tin coating with a coating weight of less than 2 g / m. 7- Process for the electrolytic manufacture of tinplate by means of the halogen process, in which Tin coatings electrolytically on opposite one another Surfaces of a strip material are deposited from an electrolyte, which contains tin (II) and fluoride ions and the coated strip material is rinsed with a detergent which contains fluoride ions and 909835/0807 dragged in from the electrolyte by means of the strip material Contains tin (II) ions, characterized that the tin is electrolytically coated on at least one of the surfaces with a coating weight of less than 2.5 g / m 2 is deposited and that a ratio of fluoride ions to tin (II) ions (F ~: Sn ⁺⁺ ) of not less than 10: 1 is maintained in the detergent. 8. The method according to claim 7 * characterized geke η η ζ eichnet that the concentration of fluoride ions in the detergent is not less than 8 g / l. 9- The method according to claim 8, characterized in that the concentration of fluoride ions in the detergent is in the range from 10 to 20 g / l. 10. The method according to any one of claims 7 W-s 9 * thereby characterized in that the ratio of the fluoride ions to the tin (H) ions (F * ~: Sn) in the electrolyte ranges from 8: 1 to 15: 1. 11. The method according to any one of claims 7 "to 10, characterized characterized in that one side is electrolytically coated with a coating weight in the range of 0.5 to 1.5 g / m is tinned. 12. The method according to any one of claims 7 T> is 11, characterized characterized in that the pH of the detergent is below 4. 13. The method according to claim 12, characterized in that the pH value is increased by adding salt 90 & 835/0807 acid to the detergent is set to less than 4. 14. The method according to any one of claims 7 Ms 13, characterized characterized in that the current density of the electrolytic tinning current is in the range of 600 ρ
Ms 1600 A per m sheet metal strip. 15- The method according to claim 14, characterized in that the current density is 800 Ms 1200 A ge ρ
m sheet metal strip. 16. Electrolytically produced, not remelted Tinplate, produced by a method according to at least one of claims 7 to 15 909835/0807