Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02558572 2006-09-01
METHOD FOR LOWERING THE COEFFICIENT OF FRICTION OF THE SURFACE
OF METAL BANDS WITH A COATING AND DEVICE FOR APPLYING A
METALLIC COATING ONTO A STEEL BAND
FIELD OF THE INVENTION
The invention relates to a method for lowering the coefficient of friction of
the surface of
metal bands with a coating, especially of tin-plated or chromium-plated steel
bands, which arc
moved with a band speed through a coating installation, as well as to a device
for applying a
metallic coating onto a steel band, especially a bond tin-plating installation
or band chromium-
plating installation.
BACKGROUND OF THE INVENTION
In the production of tinplate, especially in electrolytically operating band
tin-plating
installations, and in the production of black plate with electrolytic chromium
(EC:CS), the
metal-coated and chemically or electrochemically passivated steel plate
(tinplate with tin metal
and chromium metal + chromium III hydroxide or ECCS = electrolytic chromium
coated steel
with chromium metal + chromium III hydroxide) is greased after the coating
process in order to
lower the coefficient of friction of the coated steel plate, in order to make
it able to be better
processed during subsequent processing. For this purpose, for example, in the
production of
tinplate in band tin-plating installations, the tin-plated and passivated
steel sheet metal band is
greased electrostatically after a drying process with dioctyl sebacate (DOS),
acetyl tributyl citrate
(ATBC) or butyl stearate (BSO), typically with a deposition of 2-6 mg/m2.
Methods for lubricating the surface of coated metals, e.g., tinplate, are
described in
US 2,579,778 and US 3,826,675, with an aqueous lubricant emulsion with a pH
value between 2
and 6 produced from a weakly ionizable organic acid being used in US
2,579,778, and citric acid
ester being used in US 3,826,675.
In band tin-plating installations in which the steel sheet-metal band passes
through with a
band speed of less than 150 m/min, DOS can be deposited as an emulsion in a
mixture of, e.g.,
0.8 g/L DOS with 0.08 g/L lauryl ethoxylate in an immersion process after
passivation and after
rinsing the tin-plated steel sheet-metal band in an immersion tank. The DOS
emulsion that
adheres to the sheet-metal band surface due to the passage of the tin-plated
steel sheet-metal
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CA 02558572 2006-09-01
band through the immersion tank is then pinched off and dried with a band
drier. However, in
fast-running band tin-plating installations, in which the steel sheet-metal
band passes through the
installation at band speeds of 300 to 600 m/min, the aforementioned DOS
emulsion has proven
to be disadvantageous because of problems occurring with the distribution of
the height of the
DOS deposition over the band width, when the pinching rollers, with which the
emulsion
captured in the immersion tank was pinched, had been in use for a long time
and exhibited wear,
especially erosion at their edges.
Therefore, an objective of the invention is to provide a method for lowering
the
coefficient of friction of the surface of metal bands with a coating,
especially of a tin-plated or
chromium-plated steel sheet-metal band, in which the metal band passes through
a coating
installation at a high speed and is coated there with the metal coating, with
the method being able
to be performed with the highest possible throughput and. especially at a high
band speed.
SUMMARY OF THE INVENTION
The objectives of the invention are obtained by a method for lowering the
coefficient of
friction of the surface of metal bands with a coating, especially of tin-
plated or chromium-plated
steel bands, which are moved with a band speed through a coating installation
characterized in
that after the coating process, an aqueous solution of a tenside is sprayed
onto the coated metal
band moved at the band speed. The objectives of the invention are also
achieved with a device
for applying a metallic coating onto a steel band, especially a band tin-
plating installation or
band chromium-plating installation, with a deposition device for electrolytic
deposition of a thin
metal layer on the steel band passing through the deposition device at a band
speed, a passivation
device for passivation of the deposited metal layer, a rinsing bath for
rinsing the coated and
passivated steel band, and a processing device for reducing the coefficient of
friction of the
surface of the coated steel band, through which the steel band coated with the
metal layer passes
at the band speed, characterized in that the greasing device comprises at
least one tube arranged
at a distance from the coated steel band, with the tube having a plurality of
boreholes in the tube
jacket, through which an aqueous solution of a tenside is sprayed onto the
coated steel band
passed through the greasing device
According to the method of the invention, an aqueous solution of a tenside is
sprayed
onto the moving metal band, especially a steel band, after the coating
process, for example, after
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CA 02558572 2006-09-01
the electrolytic tin-plating in a band tin-plating installation or the
electrolytic chromium-plating
in the production of ECCS. Here, the tenside solution is sprayed onto the
metal band surface in
amounts that are so small that only a thin tenside layer composed of a few
molecular layers is
adsorbed onto the metal band surface. Here, the sprayed tenside solution is
then preferably
pinched by means of pinching rollers and then dried. After the pinching of the
tenside solution
and the drying, a tenside film with a coating of, e.g., ca. 0.1-10 mg/m2
remains on the surface of
the metal band.
The tcnside preferably involves a non-ionogenic tenside, which is sprayed onto
the
surface of the coated metal band in an aqueous solution with a concentration
of 0.01-20 g/L.
However, other tensides, especially anionic-active or cat-ionic-active and
also amphoteric
tensides, can also be used.
For spraying the aqueous tenside solution onto the metal band surface, an
arrangement
with a tube with a plurality of boreholes in the tube jacket has proven to be
advantageous. Here,
the tube with the boreholes is arranged at a distance from the metal band
surface and charged
with the aqueous tenside solution. This solution emerges through the boreholes
and is led in the
form of spraying streams onto the moving metal band. Preferably, on each side
of the metal
band, at least one such tube with boreholes is arranged, through which the
tenside solution is
sprayed onto the metal band surface opposite the boreholes. The tubes arranged
on both sides of
the metal band preferably are at a distance of 5-15 cm from the metal band
surface. The fluid
streams emerging from the boreholes of the tube intersect the surface of the
coated metal band
preferably at a right angle or especially at an angle in the range from -15
to +15 with respect to
the normal, and are pinched by one or more pinching rollers arranged behind
the intersection
point in the advancing direction of the band.
In one preferred embodiment of the method according to the invention, the
spraying of
the tenside solution is performed within a vertical tank, which has an open
outlet. In the vertical
tank, the excess tenside solution, especially the solution pinched off by the
pinching rollers, is
collected and can flow via the outlet into a storage tank underneath the
vertical tank and from
there can be supplied for reuse.
With the method according to the invention, the coefficients of sliding
friction of tinplate
and ECCS are reduced to values required by the specific application.
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In one aspect, the present invention provides a method for reducing the
coefficient of
friction of a surface of a coated metal strip which is moved through a coating
installation at a
strip speed, the method comprising after the coating operation spraying an
aqueous solution of
a surfactant on to the surface of the coated metal strip moved at the strip
speed, wherein the
aqueous solution consists of water and a surfactant, and wherein after the
aqueous solution is
squeezed off and dried a film of surfactant with a coverage of 0.1 to 10 mg/m2
is present on
the surface of the coated metal strip.
In a further aspect, the present invention provides a device for applying a
metal
coating to a steel strip, comprising: an application device for electrolytic
application of a thin
metal coating on the steel strip running through the application device at a
strip speed, a
passivating device for passivating the applied metal coating, a rinsing bath
for rinsing the
coated and passivated steel strip and a treatment device for reducing the
coefficient of friction
of a surface of the coated steel strip, through which the steel strip coated
with the metal
coating runs at the strip speed, wherein the treatment device comprises at
least one pipe
arranged a distance from the coated steel strip and having a plurality of
boreholes in the pipe
surface, through which an aqueous solution consisting of water and a
surfactant is sprayed on
to the coated steel strip moved through the treatment device, and at least one
pair of squeezing
rollers for squeezing the sprayed aqueous solution off the surface of the
coated metal strip and
a drying device for drying a film of surfactant remaining on the surface after
squeezing off.
BRIEF DESCRIPTION OF THE DRAWINGS
Below, the invention is explained in more detail with reference to an
embodiment,
with reference being made to the enclosed drawings. These show:
Figure 1, schematic view of the quenching and post-treatment of a band tin-
plating
installation for manufacturing tinplate; and
Figure 2, perspective view of a processing device of the band tin-plating
installation
from Figure 1.
DETAILED DESCRIPTION OF THE DRAWINGS
The section of a band tin-plating installation shown schematically in Figure 1
for
manufacturing tinplate includes a deposition device not illustrated here. The
steel band S
moved by a tin-plating bath is provided electrolytically with a tin coating.
The steel band S is
degreased electrolytically before the tin-plating process, rinsed with
deionized water, and then
coated with deionized water in a pickling and rinsing process. The steel band
S cleaned in this
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CA 02558572 2012-08-09
way and connected as a cathode is then led into a tin-plating bath, which
contains the
electrolytes and the tin anodes. Under continuous monitoring and regulation of
the tin-plating
conditions for high current density, a fixed, dense, and uniform tin deposit
is formed on the
steel band. Then during electrolysis after a rinsing process, the tin surface
is fluxed, i.e.,
wetted, pinched, dried, and briefly melted inductively or through resistance
heating in a
melting tower in a 20-70 C warm solution of 1 g/L HCI or 3 g/L zinc
chloride/ammonium
chloride solution, in order to achieve visual improvement of the surface
quality of the tinplate.
Then the tin-plated steel band S is led through a quenching tank 1 via a
deflection
roller U. In the quenching tank 1, there is deionized water (VE water) with a
temperature of
70-95 C. Then the steel band S is led through the passivation device 2 via
deflection rollers U
at the band speed v, which typically equals between 200 and 600 m/min. The
passivation
device 2 comprises one to two passivation tanks 2a and optionally 2b, in which
is located a
passivation fluid, for example, a 10-25 g/L sodium dichromate solution with 50-
70 C bath
temperature. The passivation can be performed electrolytically or without
current. For the
electrolytic passivation, the tin-plated steel band S is polarized as a
cathode in the passivation
device via a current roller SR and in this way is electrolytically passivated.
For the most part,
steel plates are used as anodes in the passivation bath.
4a
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Then the tin-plated and passivated steel band S is led into a rinsing bath 3
via deflection
rollers U. The rinsing bath 3 comprises, in the example in Figure 1, two
counter flow rinsing
tanks 3a and 3b, in which spraying tubes 3c, 3e are arranged in each tank in
the top region. The
deionized rinsing water is sprayed through the spraying tubes 3e onto the
steel band and then
It is also possible to use the rinsing tank 3a and 3b without spraying tubes
as opposite
current sinks, with the deionized rinsing water being filled into the rinsing
tank 3b and being led
from there into the rinsing tank 3a via an overflow. However, the amount of
rinsing water
necessary for this rinsing arrangement is greater than for the (additional)
use of spraying tubes
After the rinsing, the steel band S is led through a processing device 4 at
band speed v via
deflection rollers U for reducing the coefficient of friction of the surface
of the coated steel band
S. In the processing device 4, the coefficient of sliding friction of the tin-
plated, passivatcd, and
rinsed steel band S is reduced to the values required for later use and
processing. The processing
This arrangement is shown in detail in Figure 2. In Figure 2, the vertical
tank 5 is shown
with the outlet 6. In the vicinity of the base, there is a deflection roller
U, by means of which the
CA 02558572 2006-09-01
pump 14 with an aqueous solution of a tenside. For each tube 11, a flowmeter
15 is arranged
between the pump 14 and the tube inlet.
Behind the tubes 11 in the advancing direction v of the band (thus, above the
tubes 11 in
Figure 2), there are two pinching roller pairs I2a, 12b. The spacing of the
first pinching roller
pair 12a to the tubes 13 in the advancing direction of the band equals
approximately 20-100 cm.
The spacing between the tubes 11 and the tin-plated steel band S equals
between
1 and 50 cm and lies preferably at 5 to 15 cm. Each tube 11 has at least one
borehole or opening,
but preferably, as shown in Figure 2, there is a plurality of boreholes in the
tube jacket arranged
at a distance relative to each other in the longitudinal direction of the
tube. Preferably, each tube
has two to five boreholes with a diameter of 1 to 4 mm, preferably between 2
and 3 mm.
However, tubes with only one borehole or also with more boreholes, for
example, up to fifty
boreholes, can also be used.
The tubes 11 are charged with an aqueous solution of a tenside. The aqueous
tenside
solution emerges through the boreholes into the tubes 11 and strikes the
moving, tin-plated steel
band S in fluid streams. According to the distance of the tubes 11 from the
steel band S and the
position of the boreholcs relative to the movement direction of the steel band
S, the fluid streams
strike the steel band surface either at a right angle or at a falling or
rising angle. Preferably, the
distance between the tubes 11 and the steel band S is set and the position of
the boreholes
relative to the movement direction of the steel band is selected so that the
fluid streams intersect
at a right angle onto the steel band surface or at least within an angular
range of 45 , preferably
within an angular range of 15 , with respect to the normal (perpendicular)
band surface.
With the pinching roller pairs 12a, 12b arranged approximately 50 to 100 cm
behind the
tubes 11 in the advancing direction, the tenside solution sprayed onto the
steel band surface is
pinched off, so that a tenside layer with only a few molecular layers,
possibly only a
one-molecule tenside layer, remains on the tin-plated steel band surface.
The excess tenside solution and especially the solution pinched by the
pinching rollers 12
from the tin-plated steel band S collects in the vertical tank 5 and flows via
the outlet 6 into a
storage tank 4 under the vertical tank 5, from where the tenside solution can
be supplied for reuse
via a pump 8, in that the tenside solution collected in the storage tank 4 is
transferred to a tenside
application tank 9 and finally pumped back into the tubes 11.
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After passing through the processing device 4, the tin-plated steel band S
finally passes
into a drying device 10, which is formed by, for example, a hot-air drier, via
deflection rollers U.
With the previously described processing device 4, tin-plated steel bands were
treated
with various tenside solutions in different concentrations and tested in terms
of their coefficients
of sliding friction.
For greasing the tinplate surface, a plurality of surface-active substances
are suitable,
especially cationic, anionic, non-ionogenic, and amphoteric tensides.
Preferably, tensides arc
used that have meet legal requirements for food use according to FDA
178.9310, FDA
178.3400, and the EG guidelines 2002/72/EG and 1935//2004/EG. For non-approved
tensides,
an expensive toxicological test and approval is necessary if the steel sheets
processed according
to the invention are to be used for creating food packages. In addition to the
legal approval for
food use, also required are good wettability and adhesion of the paint used
for coating with the
tinplate surface post-treated with tenside, i.e., the tenside used must be
tailored to the paints used.
Due to the described application via spray tubes 11, the formation of foam by
the tensides that
are used does not cause interference in the post-processing of the coated
steel band.
Comparison tests with the tenside lauryl ethoxylate with 3 EO were performed
in a band
tin-plating installation that showed the suitability of the described method
for large-scale
application. This tenside is legally approved for food use according to FDA
178.9310.
It was sprayed in an aqueous solution in concentrations of 1-8 g/L after the
passivation
and rinsing in the described band tin-plating installation made from two tubes
11 on each band
side onto the tin-plated steel band S, with the two tubes 11 each having five
boreholes with a
2.5 mm diameter at a distance of 25 cm from each other in the direction
horizontal to the band
surface. The two tubes 11 were arranged ca. 80 cm in front of a pinching roll
pair 12a in the
advancing direction of the band at a distance of 10 cm from the steel band
surface. The fluid
streams extended approximately horizontally from the boreholes in the tubes 11
onto the
galvanized steel surface. The fluid streams striking the band surface were
visible in the light of a
lamp and one could see that the fluid pinched off by the pinching rollers 12
was distributed
uniformly over the width of the pinching rollers 12, detached in the form of
droplets, and finally
fell into the vertical tank 5. The tin-plated steel band samples treated in
this way were then
analyzed with a Leco C-analyzer at a maximum oven temperature of 400 C. Here,
in the scope
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of the analysis variation, tenside deposits with equal height over the width
of the steel band were
measured, which corresponded to 3 1.5 nig/1112 lauryl ethoxylate.
In further tests, by varying the band speeds v, the tenside used, and its
concentration and
various surface roughness values of the tinplate band surfaces treated in this
way, tenside film
deposits of 3 1.5 mg/m2 were detected. From this it results that the tenside-
containing solution
was pinched up to a no longer detectable fluid film of less than 0.5 niL/m2 of
the tinplate surface.
In contrast, for tenside-free rinsing water, the fluid film on the tinplate
surface is pinched off
only up to a residue of 5-10 mL/m2 on the band surface.
The tenside coating remaining on the tin-plated steel band surface after use
of the method
according to the invention is composed of the tenside deposit adsorbed onto
the band surface,
and the coating, which is produced from the thickness of the pinched fluid
film and its tenside
concentration. In comparison to tinplate rinsed conventionally (that is, with
tenside-free rinsing
water), the tinplate treated according to the method of the invention has
significantly lower
energy needs for drying in the drying device connected after the processing
device. The energy
expense for drying the tinplate band can be reduced even more if the
passivation fluid is heated
in the passivation tanks 2a, 2b and/or the rinsing water is heated in the
rinsing tanks 3a, 3b (for
example, to temperatures of 50-70 C, the rinsing water also to temperatures up
to 80 C).
The adsorption time of the tenside solution sprayed onto the band surface
according to
the method of the invention is sufficiently short to guarantee a uniform
adsorption of the tenside
film onto the tinplate surface before the pinching rollers 12 pinch the excess
tenside solution.
Due to the short adsorption time, it is presumably not necessary to spray the
fluid onto the
tinplate surface as uniformly as possible via fine spray nozzles. Instead, it
is sufficient-as
provided according to the invention-to spray the tenside solution relatively
coarsely onto the wet
tinplate surface. The advantage of spraying the tenside solution in the form
of thin fluid streams
distributed over the width of the steel band is that the risk of forming foam
in the tank, in which
the excess, especially the pinched tenside solution, collects is significantly
lower than that when
using spray tubes with nozzles, which would spray the tenside solution in a
fine mist onto the
tinplate surface. The larger borehole diameters of the spray tubes tend to
accumulate less foreign
matter than do the smaller diameters of the spray nozzles required for the
same application.
The tinplate bands examined in the comparison tests were examined with a three-
ball
tribometer in terms of their coefficient of sliding friction before and after
the treatment according
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to the invention. Here, the following coefficients of sliding friction were
determined for
electrochemically passivated tinplate with 2.8 g/m2 tin deposit and stone-
finish surface:
without slip additive: = 0.40
with 2 mg/m2 lauryl ethoxylate: p. = 0.24
with 4 mg/n12 dioctyl sebacate (DOS): p. = 0.20
The tenside deposit does not reduce the sliding friction of the tin surface as
much as does
the DOS deposit. However, the sliding friction is good so that scratches and
scrapes are not
created on the tinplate surface when the tinplate rings break apart and the
tables in the next
post-processing stage can be cleared of packages without a problem.
However, in contrast to conventional electrostatic greasing of the tinplate
surfaces with
esters such as DOS, in the tinplate bands treated according to the invention,
no tin dust caused by
production has been observed. In contrast, especially for tinplate greased
with DOS, a dust layer
due to production is often observed, which is problematic, because it can be
removed only
through suitable, complicated, and careful measures during the installation.
The reason for the
freedom from dust in the method according to the invention can be traced
possibly to the rinsing
effect of the tenside solution in the application after the passivation and
rinsing, as well as to the
better adhesion of the tinplate to the surfaces of the non-driven deflection
rollers in the second
loop tower of the band tin-plating installation. Due to the low slippage of
the tinplate with the
deflection rollers in the loop tower, in contrast to greasing with
conventional substances such as
DOS, obviously no tin particles are rubbed off.
Another advantage over greasing tinplate conventionally, for example, with
DOS, ATBC
(acetyl tributyl citrate) or BSO (butyl stearate oil), is the ability for
perfect (pore-free) painting of
the tinplate surfaces treated according to the invention after typical storage
times (for example,
more than 12 months). This advantage can be explained presumably in that the
adsorbed tenside
molecules do not coagulate into droplets, as is often the case for DOS
greasing with >4 mg/m2 in
the edge region of the tinplate tables. Paint, which cannot completely
dissolve these droplets in
the wet film on the tinplate surface, then tends toward formation of pores in
the paint layer.
The method according to the invention can also be applied in band tin-plating
installations with horizontal rinsing cascades. In these horizontal rinsing
cascades, rinsing water
is sprayed through spray registers with nozzles onto both band surfaces for
each rinsing stage up
to 40 m3/h. The rinsing water is then pinched off and flows back into a
storage tank under the
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CA 02558572 2012-08-09
corresponding rinsing stage, from where it is pumped back into the horizontal
rinsing stage. In
these horizontal rinsing cascades, the method according to the invention can
be used when the
spray registers before the last pinching roller pair is replaced by the
aforementioned tubes with
boreholes, with which the aqueous tenside solution according to the invention
is sprayed onto
one or both band surfaces. For two-sided spraying of the tin-plated steel
band, the tenside
solution is sprayed first through a tube arranged above the top side of the
band. Second, the
aqueous tenside solution is sprayed onto the bottom side of the band, by
spraying the tenside
solution through a tube with boreholes on the pinching roller adjacent to the
bottom side of the
band. In this way, the aqueous tenside solution is transported through the gap
between the
steel band and the pinching roller adjacent to the bottom side of the band,
where the fluid
mixes with the water film on the bottom side of the band and the band surface
is "greased" in
this way with the tenside film. Here, the pinched off tenside solution also
flows back into a
storage tank-as in the described embodiment of the band tin-plating
installation with a vertical
tank - and can then be reused.
The method according to the invention applied in the processing device 4 of
the
described band tin-plating installation can be used very generally for
reducing the coefficient
of friction of metal bands with a metallic coating, e.g., also special
chromium-plated steel
bands (ECCS).
Examples:
In the laboratory, black plate sheets with a stone finish surface with 17 x 20
cm area
were
- degreased electrolytically in an alkaline solution
- rinsed with deionized water
- pickled in 100 g/L sulfuric acid solution
- rinsed again with deionized water and
- electrolytically tin-plated in a tin methane sulfonate bath with
commercially available
bath additives (replenisher and stanguardTM by Rohm & Haas) with 2 A/dm2
current density
(tin deposit 2.8 g/m2).
The tin-plated sample was
- rinsed with deionized water and
CA 02558572 2006-09-01
- electrolytically passivatcd in a 25 g/L sodium dichromate solution (T = 60
C; i =
1.5 Adm-2, t = I sec). The total chromium deposit of the passivation layer
equaled 5 mg/m2. The
sample was again thoroughly
- rinsed with deionized water
- fixed in a paint centrifuge (Erichsen) and spun for 5 seconds at 1000 rpm
the tin surfaces were covered with aqueous solutions of 1 g/L of the following
tcnsides, and the
tenside solution was spun for 5 seconds at 1000 rpm:
(designated below as post-processing product X (with X = A, B, C, D)
lauryl ethoxylate with 3 EO
B: C12-14 carboxylic acid ethoxylate with 9 EO
C: C10-12 alkane sulfonic acid, Na salt,
D: polyethylene oxide (average molecular weight 6000 Dalton)
The samples were removed from the paint centrifuge and dried with hot air.
On the samples with the various tenside coatings, the following tests were
performed:
- tin deposit
- total chromium deposit in the passivation layer
- tenside deposit (C contents of the tenside with the Leco carbon measurement
device
RD 412)
- sliding friction
- painting with 5 g/m2 epoxide resin paint PPG 3907-301/A
- sterilization in the following solutions:
- 3% ethanoic acid 30 min at 100 C
- 1% hydroxypropionic acid + 2% NaCl 30 min at 121 C
- 0.5 g/L cysteine 90 mm at 121 C
- 1.0 g/L cysteine 90 min at 121 C
The painting adhesion was tested after the steriliz:ation test through a cross-
cut adhesion
test and tesa test according to EN ISO 2409.
The tinplate samples greased with the various non-ionogenic tensides also had
low
organic deposits with 55 mg/m2 like tinplate samples greased electrostatically
with dioctyl
sebacate in a band tin-plating installation (desired deposit in the tinplate
production at industrial
scale: 4 2 mg/m2 DOS).
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The tin oxide deposits and the chromium deposits of the tinplate samples
passivated in
sodium chromate solution were within the desired range of commercial tinplate
production.
With lu = 0.13-0.24, the sliding friction of the tinplate samples greased with
tcnside or
DOS lay significantly under the sliding friction of ungreased tinplate with pt
= 0.4. The tinplate
samples with sliding friction in the range of p. = 0.13-0.24 have the same
good sliding ability in
further processing through painting and shaping in production.
The paint adhesion of the tinplate sample painted with 5 g/m2 paint PPG 3907-
301/A and
sterilized in various solutions was just as good for the greasing with tenside
as for the greasing
with DOS.
[Note: commas should be read as decimal points.]
Running Product for treatment tin coating passivation tin-
oxide tenside Sliding
No. after coating (g/m2) (mg/m2/Cr) coating coating
friction
(C/m2) (mg/m2 C)
coefficient
1 A 2,8 5,0 15 2,3 0,24
1 2 B 2,9 4,8 20 2,7 0,24
__________________________________________________________________________ ¨I
, 3 C 2,8 5,8 15 3,8 0,18 I
__________________________________________________________________________ 1
4 D 2,7 4,5 18 3,5 0,13
1
Reference sample, tinplate, electrostatically greased with DOS (mg/m2)
5 Dioetylsebacat (DOS) , 2,8 5,4 18 3,5 0,22
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No.. Product for treatment- Sterilization resistance after varnishing
with
after coating 5 g/m2 varnish PPG 3907-301/A; result of the
cross-cut adhesion test*
3% ethanoic 1% lactic acid 0,5 g/lCystein
1,0 gil Cystein
acid + 2% NaC1
30 min/121 C 90 min/121 C 90 min/121
C
30 min/100 C
1 A GT 0 GT 0 GT 0 GT 0
2 B GT 0 GT 0 GT 0 GT 0
3 C GT 0 GT 0 G'1' 0 GT 0
4 D GT 0 GT 0 GT 0 (3T 0
Reference sample, tinplate, electrostatically greased with DOS
5 Dioctylsebacat (DOS) GT 0 GT 0 GT 0 GT 0
* cross-cut adhesion test according to DIN EN 2409.
13
