Note: Descriptions are shown in the official language in which they were submitted.
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Protective Glove with a Textile Lining
Description
Field of the Invention
The invention relates to protective gloves, in particular
elastic, polymeric protective gloves with a textile lining,
as well as to a method for their manufacture.
Background of the Invention
Because of the availability of a number of suitable
polymers, it is possible to obtain protective gloves for a
large number of chemical substance classes. It is thus
possible, depending on the polymer or polymeric composite
materials used, to obtain long permeation times for
different substance classes. In particular, elastomers such
as isoprene rubbers also feature a low gas permeability,
which is desirable from a safety standpoint. Consequently,
however, protective gloves composed of polymeric materials
are not breathable, i.e. the moisture generated by
perspiration remains inside the glove. This has a
significant negative impact on the wearing comfort of such
a protective glove, particularly when it is worn for long
periods. To improve the wearing properties, in particular
to absorb moisture, therefore, textile inner gloves are
generally used. The use of a textile inner glove and a
separate polymeric protective glove, however, is
disadvantageous for practical reasons. On the one hand, it
takes a relatively long time to put on the inner glove and
the protective glove. On the other hand, the use of two
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gloves results in a relatively large overall thickness of
the glove combination, which has a disadvantageous effect
on tactile sensitivity. There is also often a lot of play,
i.e. space between the textile inner glove and the
polymeric glove, which likewise has a disadvantageous
effect on tactile sensitivity.
There is thus an interest in polymeric protective gloves
with a fixed textile lining. In this connection, there are
protective gloves known from the prior art in which the
textile lining is glued into the polymer protective glove,
i.e. an adhesive agent is used to affix the lining in the
glove. The textile lining and the polymeric material,
however, do not have a common phase boundary and the
adhesion is produced by means of the adhesion and cohesion
forces of the adhesive agent, for example a glue. The
gluing process is disadvantageously complex and the textile
lining and polymer glove come unglued from each other
relatively easily. The latter is particularly true when the
bonding agent is washed out over the course of the wearing
life or is subject to other external influences.
By contrast, a protective glove made of a composite
material composed of a textile knitted fabric and a polymer
layer has a more powerful adhesion between the textile knit
and the polymer layer.
German patent disclosure DE 27 59 008 Al describes a
protective glove composed of a textile that has been coated
by means of a dip-coating process from a dispersion with
polymers such as polyvinyl chloride (PVC) and also
describes its manufacturing method and an apparatus
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conceived for this purpose. Due to the irregular layer
thicknesses and the occurrence of diffusion conduits, so-
called "pin holes," a protective glove of this kind has a
comparatively poor protective effect. This is also
disadvantageous from an economic standpoint because it
results in a larger number of rejects. It also requires the
use of additives such as coagulation reagents.
General Description of the Invention
The object of the invention is to create a polymeric
protective glove with a textile lining, which has uniform
permeation times across the entire surface of the glove and
thus has a reliable protective effect in relation to a
variety of chemical compound classes.
Another object is to create a glove of this kind that also
has a high level of wearing comfort while maintaining
flexibility and tactile sensitivity. Another object is to
create an efficient method for manufacturing a protective
glove of this kind.
This object is attained by the subject of the independent
claims. Advantageous embodiments and modifications are
disclosed in the respective dependent claims.
Accordingly, the invention provides a polymeric protective
glove with a textile lining in which the textile lining and
at least a first polymer layer are embodied in the form of
a layered laminate. The first polymer layer includes a
synthetic elastomer, which is embodied in the form of a
copolymer with isoprene as a monomer unit, i.e. the
elastomer contains isoprene monomer units. In the context
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of the invention, copolymers are understood to be polymers
with at least two different monomer units. An isoprene
monomer unit is understood in particular to be the
repeating unit I. Polymers with isoprene monomer units are
understood to also include those polymers in which
derivatives of isoprene monomer units are present. In
particular, such polymers are understood to be polymers
with isoprene monomer units in which a derivatization has
taken place by means of polymer analogous reactions such as
halogenation of the polymer.
-N
*
The textile layer of the layered laminate forms the inside
of the glove and is understood to be the bottom (innermost)
layer. Consequently, the first polymer layer, like
optional, subsequent additional polymer layers situated
over the said layer, i.e. relative to the glove as it is
worn by the user, is situated toward the outside. The
layered laminate is constructed so that the textile layer
and the first polymer layer are firmly bonded to each other
by means of a common boundary layer. The textile layer here
can, for process-related reasons, also contain additives or
residual amounts of additives such as sizing agents or
film-forming substances, in particular polyvinyl alcohol
(PVA) or a polysaccharide such as starch.
In a preferred embodiment of the invention, the textile
layer and the first polymer layer are held together by a
fiber reinforced material layer, i.e. a fiber/synthetic
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composite. This permits a particularly good adhesion of the
first polymer layer to the textile lining or textile layer.
In particular, it is thus possible to dispense with using
an adhesive agent, in particular a glue. The textile
properties of the textile lining are thus largely
preserved.
On the common boundary layer, the lining and polymer layer
form a fiber reinforced material in which the fibers of the
textile layer are embedded into a matrix of the polymer of
the first polymer layer. The fiber reinforced material is
produced when the textile lining or textile layer is dipped
into a solution of a synthetic rubber with isoprene monomer
units. At the boundary layer of the two layers, the polymer
solution penetrates into the textile layer and envelops the
fibers. The textile layer is thus at least partially
penetrated by the polymer layer. An entanglement of the
textile fibers with the polymer chains occurs. This
increases the contact area between the fibers and the
polymer chains and thus also increases the inter- and
intramolecular forces of attraction that can be due to
interactions such as van-der-Waals forces or adhesion
effects.
Preferably, the textile lining is composed of a knitted
fabric. It is advantageous if, in addition to the first
polymer layer, the textile layer or textile lining is
elastic.
The knitted fabric is preferably a knitted fabric with
double loops; an interlock knitted fabric is particularly
preferable. This is advantageous for producing a fiber
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reinforced material while preserving the textile properties
of the lining since the knitted fabric has a sufficient
mesh density, which has a positive effect on the degree of
impregnation of the textile lining.
In an advantageous embodiment of the invention, the knitted
fabric of the textile lining contains cellulose-containing
fibers. It is particularly advantageous if the knitted
fabric is composed of cotton or a cotton blend fabric, in
particular with a cotton content of greater than 50%. This
is advantageous because natural fibers, in particular
cellulose-containing fibers, are particularly able to
absorb moisture due to their swelling capacity.
It is advantageous if the cotton fabric has a density of
greater than 150 g/m2, in particular greater than 250 g/m2.
The yarn size of the yarn used is preferably 30 : 1.
It has turned out that the penetration of the textile
lining can be influenced by means of the density of the
knitted fabric in combination with the yarn size.
In one embodiment of the invention, the first polymer layer
contains an elastomer with butyl monomer units. It is thus
possible to achieve a protective effect in relation to a
multitude of compound classes. Thus, elastomers with
isoprene monomer units such as cross-linked butyl rubbers
(IIR), in particular elastomers with butyl monomer units,
have a good protective effect in relation to polar solvents
and in relation to acids and bases. Low glass temperatures
Tg result in a very good flexibility, even at low
temperatures. Moreover, elastomers with isoprene units have
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a low gas permeability, i.e. they are impermeable to a
multitude of gases such as hydrogen chloride or ammonia.
In a preferred embodiment of the invention, the first
polymer layer contains an elastomer with halogenated butyl
monomer units, in particular an elastomer with butyl
monomer units that has been halogenated in a polymer
analogous reaction. It is particularly preferable for the
first polymer layer to contain an elastomer with bromobutyl
monomer units; in the context of the invention, bromobutyl
monomer units are understood in particular to be the
repeating units
II, III, :r and
* \
IV.
Br
:r
II III IV
Compared to their pure hydrocarbon derivatives, halogenated
butyl rubbers are easier to cross-link because of their
lower bond energies. This effect is particularly pronounced
in rubbers with bromobutyl monomer units. In addition, a
halogenation of the butyl rubber increases its chemical
inertness and thus increases the protective effect of the
glove.
According to one embodiment of the invention, the first
polymer layer is applied to the textile layer by means of a
dip-coating process, i.e. a dipping process, in particular
a dip-coating process from a solution. This is advantageous
since it makes it possible to dispense with additives such
as coagulation reagents. In addition, polymer layers
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applied by dip-coating processes from solutions have
consistent layer properties. It is thereby possible to
ensure constant permeation times over the entire glove and
thus a reliable protection. It is likewise possible to
avoid the occurrence of so-called pin holes, i.e. diffusion
conduits, in the polymer layer.
Preferably, the first polymer layer is composed of two
polymer sublayers: the first polymer sublayer contains no
colorant, the second polymer sublayer contains colorant,
and the second polymer sublayer is disposed onto the first
polymer sublayer. This embodiment of the first polymer
layer is particularly advantageous since uncolored, i.e.
light-colored, textile linings are typically used for
protective gloves. Because an uncolored first polymer
sublayer is used, the sublayer glistens through the textile
lining without influencing the color impression of the
lining. On the other hand, users especially prefer
protective gloves in which colorants have been added to the
polymer layer; hence, the established position of such
gloves in the marketplace.
In an advantageous modification of the invention, at least
one second polymer layer of another, different polymer is
applied over the first polymer layer. In another preferred
embodiment, the second polymer layer contains a fluorinated
elastomer. Repulsive, i.e. repelling, interactions sharply
reduce an adsorption of molecules on the layer surface,
thus increasing the resistance to a large number of
chemical substance classes. Consequently, the comparatively
high grease, oil, and fuel permeability of the first
polymer layer's elastomer with isoprene monomer units can
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be compensated for through combination with the second
polymer layer.
Such a protective glove made of a composite material of
different polymer layers, in particular a layered laminate
composed of an isoprene elastomer and a fluoroelastomer,
due to synergistic effects, offers a broader range of
protection, i.e. high permeation times for a large number
of compound classes, than corresponding protective gloves
with only one polymer layer.
In an advantageous modification of the invention, the
second polymer layer contains an elastomer with 1,1-
difluoroethylene monomer units. Fluoroelastomers with 1,1-
difluoroethylene monomer units are inert in relation to
many chemicals, oils, and fuels and are heat resistant. The
high tear resistance of up to 20 MPa of fluororubbers with
1,1-difluoroethylene monomer units also results in a high
mechanical resistance of the polymer composite material.
In a particularly advantageous embodiment of the invention,
the second polymer layer contains a copolymer with the
monomers 1,1-difluoroethylene and hexafluoropropene.
In another preferred embodiment according to the invention,
the second polymer layer contains an elastomer with
acrylonitrile monomer units such as a cross-linked nitrile
rubber (NBR).
Preferably, the protective glove has a first polymer layer
with a thickness of 0.05 mm to 0.5 mm and/or a second
polymer layer with a thickness of 0.05 mm to 0.15 mm. This
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has a particularly advantageous effect on permeation times,
flexibility, and wearing comfort.
The manufacturing method is composed of at least the
following steps:
In step a), a textile lining is placed onto a glove form.
In this case, it is advantageous to use an anti-friction
agent such as a silicone oil, which is applied to the glove
form in advance. In the next step b), a solution of a film-
forming polymer is applied to the textile lining that has
been placed onto the glove form. In order to produce a
first polymer
layer, in step c), a glove form is dipped into a first
solution of a synthetic, first rubber. In order to prevent
a cross-linking of the rubber either in the solution or
immediately after removal of the form, the temperature Ti
during the dip-coating procedure is lower than the cross-
linking temperature of the first rubber. After a predefined
dipping time, i.e. immersion time, the glove form is
removed from the first solution (step d)). Steps c) and d)
are carried out once or several times in sequence. The
dipped first polymer layer is dried (step e)). Preferably,
the drying time is at least 8 hours. Then in step f), the
first polymer layer is vulcanized by autoclaving the
protective glove. In the next step g), the protective glove
is removed from the form.
In an advantageous embodiment of the method according to
the invention, in step c), the glove form is dipped into a
first solution of a butyl rubber, preferably a first
solution of a halogenated butyl rubber, and particularly
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preferably a first solution of a rubber with bromobutyl
monomer units.
In a modification of the invention, after step e), the
glove form is dipped into a second solution of a second,
other synthetic rubber. After a predefined dipping time t2,
the glove form is removed from the solution and dried. In
particular, the first and second polymer layers are jointly
vulcanized in step f).
It is particularly advantageous if the second solution
contains a rubber with the monomers 1,1-difluoroethylene
and/or hexafluoropropene. This has a positive effect on the
properties of the glove, for example on the permeation
times for a multitude of chemical compound classes.
Usually in the solvent dipping process, i.e. a dip-coating
process from a solution, however, longer immersion times
are required than in the corresponding dispersion process.
When a textile lining is dipped for a long time, this
typically results in a partial or even total penetration of
the textile lining and thus in a loss of the desired
textile properties of the lining. Pre-treating the lining
with a film-forming polymer can prevent a complete
impregnation of the textile lining, even with longer
dipping times. It is thus possible to dip polymer layers
into solutions while still maintaining the desired textile
properties of the lining.
In particular, polar polymers with hydroxyl groups are used
as film-forming polymers. Preferably, these polymers are
water-soluble. In particular, a PVA solution and/or a
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polysaccharide-containing solution such as a starch-
containing solution are used as a solution of a film-
forming polymer. Preferably a plasticiser, in particular
glycerin, is added to the film-forming polymer solution.
Surprisingly, it occurred that according to one embodiment,
a spraying or a single or multiple brushing or dabbing of
the textile lining with a cloth impregnated with the
solution of the film-forming polymer can prevent a complete
penetration with the rubber solution. It is thus possible
to prevent a complete penetration of the textile lining.
This effect is particularly pronounced with cellulose-
containing textiles. Cellulose-containing fibers such as
cotton fibers swell significantly in the presence of
moisture and absorb the moisture. The application of the
film-forming polymer thus makes it possible to optimally
pre-treat these fibers for the subsequent dip-coating
procedure.
In one embodiment, before being dipped into the first
solution of a rubber with isoprene units, the textile
lining is brushed with the PVA solution until the amount of
application of PVA onto the lining totals 0.15 to 3 g,
preferably 0.3 to 1.8 g, particularly preferably 0.6 to 0.9
g. It is thus possible to influence the degree to which the
rubber impregnates the textile lining.
According to an alternative embodiment, the textile lining
is sprayed with a solution containing a polysaccharide such
as starch. This solution preferably functions as a sizing
agent. The use of a polysaccharide, in particular starch,
as a film-forming polymer has the advantage that the
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protective glove does not stick very powerfully to the
glove form. As a result, after production, the glove can
surprisingly be removed from the glove form even without
turning it inside out, which significantly improves the
production process.
In one embodiment of the method according to the invention,
the viscosity of the first rubber solution is from 100 to
200 s (determined with a 6 mm Ford beaker). This is
advantageous because a rubber solution with a high
viscosity, due to its flow behavior, penetrates more slowly
into the textile lining than corresponding solutions with
lower viscosities. Consequently, the selection of the
viscosity of the first rubber solution constitutes a
further parameter which, in combination with the film-
forming polymer, can be used to influence the degree of
penetration.
In a modification of the invention, the textile lining is
dipped into two different solutions of the same first
synthetic rubber, which differ in terms of their
viscosities. First, the textile lining is dipped according
to process steps c) and d) into a solution of the first
synthetic rubber with a high viscosity. This produces a
first polymer sublayer, which does not completely penetrate
the textile layer and seals the surface of the textile
lining on the outside. In the subsequent dip-coating
according to process steps c) and d), the dipping takes
place in a second solution of the first synthetic rubber
with a lower viscosity, thus contributing to a further
build-up of the first polymer layer. This is particularly
advantageous for process-related reasons since rubber
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solutions with comparatively low viscosities are easier to
work with when dip-coating from a solution.
In at least one of the dip-coating procedures, the glove
form is preferably dipped partially at least once and then
is dipped all the way. This makes it possible to achieve
uniform layer thicknesses also with glove forms in which
this would not otherwise be possible due to their geometry,
for example in glove forms with sleeves that widen out in
the direction of the glove opening. The partial dipping is
also advantageous in terms of the degree of penetration of
the textile layer. By initially pre-dipping only the hand
region, it is possible to select a reduced dipping depth.
As a result, the hydrostatic pressure is lower during the
first dip-coating procedure. This effect is particularly
observable at the finger tips. Each dip-coating procedure
of the glove form into the same rubber solution produces
another layer of the rubber, which is referred to as a
dipped polymer sublayer. After a dipped polymer sublayer
has been deposited in the first partial dipping procedure,
which seals the textile lining up to approximately the
wrist, then a full dipping can occur, i.e. with a higher
hydrostatic pressure at the fingers, without this
disadvantageously affecting the impregnation depth of the
textile lining.
A preferred embodiment of the invention provides a method
in which the polymer layers are dipped as often and for as
long as necessary until the first polymer layer has reached
a thickness of 0.05 to 0.5 mm and/or the second polymer
layer has reached a thickness of 0.05 to 0.2 mm.
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The vulcanization of the first polymer layer preferably
occurs by means of autoclaving at a pressure of 3 to 5 bar
and/or at a temperature of 60 to 170 C, in particular at a
temperature of 90 to 150 C. A cross-linking of rubbers into
elastomers increases their mechanical resistance
significantly. In addition, the cross-linking reduces the
permeation rates within the cross-linked polymer layers.
It is advantageous to wash the removed protective gloves
with water to which tensides have preferably been added.
Residues of PVA and/or starch that are not enveloped by the
first polymer layer can thus be at least partially removed
from the textile lining. However, one advantage in the use
of starch as a film-forming polymer lies in the fact that
it is possible to dispense with the use of rinsing agents
when removing the protective glove from the glove form.
Furthermore, the starch can remain in the textile lining
without a significant, negative impact on the wearing
comfort, so that it is possible to dispense with an
additional step of washing out the finished protective
glove, thus making it possible to increase productivity.
The invention will be described in greater detail below in
conjunction with an exemplary embodiment and with reference
to the figures; some elements that are the same or similar
have been provided with the same reference numerals.
Brief Description of the Figures
Fig. 1 is a schematic depiction of the manufacturing method
of the first exemplary embodiment,
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Fig. 2 is a schematic depiction of the manufacturing method
of the second exemplary embodiment,
Fig. 3 is a schematic depiction of the manufacturing method
of the third exemplary embodiment,
Fig. 4 is a schematic depiction of the protective glove
according to the invention,
Fig. 5 is a schematic cross-section through the composite
material of a protective glove with the glued-in textile
lining,
Fig. 6 is a schematic cross-section through the detail A of
the first exemplary embodiment,
Fig. 7 is a schematic cross-section through the detail A of
the second exemplary embodiment,
Fig. 8 is an optical microscope image of the cross-section
through the detail A of the first exemplary embodiment.
Detailed Description of an Exemplary Embodiment
Fig. 1 schematically depicts the manufacturing method of a
protective glove 16 in conjunction with the first exemplary
embodiment. Fig. 2 shows a simplified form of the
manufacturing method, which is explained in greater detail
in conjunction with a second exemplary embodiment. Fig. 3
shows another embodiment of the manufacturing method. Fig.
4 is a schematic depiction of the protective glove 16
according to the invention. The upper part of the
protective glove 16 is composed of the fingers 17, the
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palm, and the back of the hand and at the wrist 18,
transitions into the sleeve 19 of the glove. The inside of
the protective glove 16 is composed of the textile lining
2. The layer structure of the layered laminate of the two
exemplary embodiments will be described in greater detail
in conjunction with detail A in Figs. 5 and 7.
The method schematically depicted in Fig. 1 for
manufacturing the first exemplary embodiment includes the
following steps:
A glove form 1 composed of ceramic is brushed with silicone
oil. Then a textile cotton lining 2 is pulled on over the
glove form 1. A cloth that is impregnated with a PVA
solution is used to apply 3 to 4 coats of the aqueous PVA
solution 3 to the textile lining 2. To produce the PVA
solution 3, first 3.75 kg of PVA are dissolved in 25 liters
of demineralized water at 90 C. For the ready-to-use
solution 3, 1 liter of the parent solution was mixed with
500 ml glycerin and 5 liters of demineralized water. The
PVA solution 3 is in particular applied from the finger
tips 20 to the wrist 18 by wiping with a cloth, leaving out
the sleeve of the glove 19. Then the lining is dried at
room temperature. In a heated dipping case 4, the glove
form 1 is dipped into a dipping reservoir 5 of a first
solution of a synthetic first rubber 6. The solution
temperature of the solution of the synthetic first rubber 6
is Tl = 30 C during the dipping.
The first solution of a synthetic first rubber 6 contains
bromobutyl rubber and toluene as a solvent. No colorants
were added to the first bromobutyl solution 6. The first
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bromobutyl solution 6 has a viscosity of 100 to 200 s
(determined with a 6 mm Ford beaker) during the dipping. In
a first dip-coating procedure, the glove form 1 is
partially dipped into the first bromobutyl solution 6 from
the finger tips 19 to the wrist 18 and in the subsequent
dip-coating procedures, is dipped into it all the way, i.e.
including the sleeve 19. In the first dip-coating
procedure, the partial dipping causes a lower hydrostatic
pressure to act on the textile lining, in particular on the
fingers 17 and the finger tips 20, than would occur in a
complete dipping. It is thus possible to reduce the
penetration of the textile lining 2 by the first bromobutyl
solution 6. After the drying of the first dipped polymer
sublayer thus produced, the surface of the textile lining 2
is sealed, thus permitting the dipping in subsequent dip-
coating procedures to be carried out with higher
hydrostatic pressure at the fingers 17 and the finger tips
20. The dipping is carried out as often and for as long as
necessary until the dipped polymer sublayers produced in
the individual dipping procedures combine to reach a
thickness of approximately 0.1 mm and thus constitute the
first polymer sublayer 26 of the first polymer layer 25.
For the dipping of the glove form 1 in the bromobutyl
solution 6, the lifting device 7 raises and lowers the
dipping reservoir 5. After each dip-coating procedure, the
glove form 1 is dried under rotation for a period of 30
minutes at 30 C.
The polymer layer 26 deposited in the first bromobutyl
solution 6 and composed of a plurality of polymer dipped
sublayers (not shown in detail in Figs. 6 and 7) is white.
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The glove form 1 is dried for at least 8 hours at 25 to
30 C in order to remove the solvent.
Then, in a second heatable dipping casing 8, a dip-coating
in a second solution 10 of the synthetic first rubber
contained in a dipping reservoir 9 is carried out. The
solution temperature of the second rubber solution 10 is
30 C. The second solution of the synthetic first rubber 10
thus likewise contains bromobutyl rubber dissolved in
toluene. In addition, the second bromobutyl solution 10
contains carbon as a colorant. The viscosity of the second
bromobutyl solution 10 is from 50 to 120 s (determined with
a 6 mm Ford beaker). The glove form 1 is dipped into the
second bromobutyl solution 10 in three full-immersion dip-
coating procedures until the dipped polymer sublayers
deposited in this way (not shown in detail in Figs. 6 and
7) combine to produce the second polymer sublayer 27 of the
first polymer layer 25 and have a thickness of
approximately 0.05 mm. After each dipping procedure, the
glove form 1 is dried under rotation. After the last dip-
coating procedure in the second bromobutyl solution 10, the
glove form 1 is dried for 12 hours at room temperature.
Then in a heatable dipping casing 11, the glove form 1 is
dipped into a dipping reservoir 12 containing a third
rubber solution 13. Here, too, the glove form 1 is not
moved, but instead, the lifting device 7 moves the dipping
reservoir 12. The third solution of a synthetic third
rubber 13 contains a rubber with the monomers 1,1-
difluoroethylene, hexafluoropropene, and
tetrafluoroethylene, e.g. Vitone. Methyl ethyl ketone is
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used as a solvent. The temperature T2 of the Viton
solution 13 is T2 = 25 C during the dip-coating procedure.
After a predefined dipping time, the glove form 1 is
removed from the dipping reservoir 12 and dried for 30
minutes at a temperature of 25 C under rotation in the
dipping casing 11. The above-described process of dipping
in the Viton solution 13 and the subsequent drying
procedure are repeated 3 to 5 times until the layer
thickness of the Viton layer serving as the second polymer
layer 27 is approximately 0.1 mm. In order to remove the
methyl ethyl ketone completely, the glove form 1 is dried
for 12 hours at room temperature. Then, the coated glove
form 1 is vulcanized in an autoclave 14 for 120 minutes at
a pressure of 3 bar and a temperature of 150 C. Thus, the
first polymer layer 25 and the second polymer layer 28 are
jointly vulcanized as a layered laminate 29 composed of
different polymers.
Fig. 2 shows the manufacturing method of a second exemplary
embodiment. The second exemplary embodiment has only the
first polymer layer 25 and thus constitutes a simplified
form of the first exemplary embodiment described above.
Here, too, the manufacturing method includes preparing the
glove form 1, pulling on the textile lining 2, and coating
it with a PVA solution 3. These steps are performed in
accordance with the manufacturing method of the first
exemplary embodiment. By contrast with the first exemplary
embodiment, however, dipping is only carried out in the
bromobutyl solutions 6 and 10 according to the
manufacturing method of the first exemplary embodiment.
After the last dip-coating procedure in the bromobutyl
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solution 10, the glove form 1 is dried at room temperature
to completely remove the methyl ethyl ketone. The coated
glove form 1 is then vulcanized in an autoclave 14 for 120
minutes at a pressure of 3 bar and a temperature of 150 C.
Fig. 3 shows a third exemplary embodiment of the
manufacturing method. The difference from the first
exemplary embodiment (Fig. 1) lies in the use of a starch-
containing solution 15 in lieu of the PVA solution 3. For
example, the starch-containing solution is a conventional
ironing or laundry starch solution thinned 1 : 1 with
water.
Consequently, it is preferable for PVA and/or starch to be
used as the polar polymer with hydroxyl groups. Before the
first dip-coating procedure, the textile lining 2 in this
case is sprayed with the starch-containing solution and is
then dried in an oven (30) until the water of the starch-
containing solution has completely evaporated, for 20
minutes at 80 Celsius in the example. The subsequent
process steps are performed analogously to the first
exemplary embodiment.
The layer structure of the first exemplary embodiment is
schematically depicted in Fig. 6; dipped polymer sublayers
are not shown in detail. The protective glove 16 according
to the invention and the composite material according to
the invention are composed of a textile layer or the
textile lining 2 and the first polymer layer 25, which
partially penetrates the textile layer 2. Consequently,
unlike the protective glove with the glued-in lining 2
schematically depicted by way of example in Fig. 5, the
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composite material according to the invention does not have
a adhesive agent layer 22. The partial penetration of the
textile lining 2 by the first polymer layer 25 produces a
mechanical entanglement of fibers and rubber, which is
fixed in place in place by the vulcanization of the rubber.
In this case, the penetration only goes so deep, as a
result of which the textile properties of the lining 2 are
at least partially preserved.
The textile layer or textile lining 2 forms the inside of
the glove. The arrow 23 symbolizes the chemical action on
the protective glove 16 from the outside.
In the first exemplary embodiment, in addition to the
textile layer 2 and the first polymer layer 25, which is
composed of the two polymer sublayers 26 and 27, the
layered laminate of the protective glove 16 is also
composed of a second polymer layer 28, as schematically
depicted in Fig. 6.
The textile lining 2 of the exemplary embodiment contains
cotton fibers. The cotton content is > 50%; the lining can
be a cotton blend fabric or a pure cotton knitted fabric.
The knitted fabric is embodied as an interlock knitted
fabric and has a weight of 265 g/m2 with a yarn count of
30.
The first polymer layer 25 is composed of bromobutyl rubber
and has a layer thickness of 0.15 mm. This bromobutyl layer
25 not only acts as a barrier to liquid media, but also has
a very low gas permeability. Consequently, the bromobutyl
layer 25 provides protection from gases such as ammonia or
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hydrogen chloride. The second polymer layer 28 contains a
fluoroelastomer with the monomers 1,1-difluoroethylene and
hexafluoropropene and possibly also tetrafluoroethylene,
e.g. Viton0. The Viton0 layer 28 has a layer thickness of
0.1 mm. The combination of the bromobutyl layer 25 and the
Vitone layer 28 in the layered laminate 29 makes it
possible to achieve a protective effect that goes beyond
the cumulative action of the two individual layers. The
exemplary embodiment has long permeation times for a
multitude of compound classes such as aliphatic
hydrocarbons, acids, bases, and polar organic compounds
such as amines and polar solvents. The textile lining 2
simultaneously ensures a high level of wearing comfort
without having a negative impact on tactile sensitivity or
flexibility of the protective glove 16.
Fig. 8 shows an optical microscope image of the cross-
section A of the second exemplary embodiment described
above. The textile lining 2 forms the inside of the glove.
The bromobutyl layer 25 and the textile lining 2 thus form
a composite material. The white, i.e. uncolored, first
bromobutyl sublayer 26 here partially penetrates the
textile layer 2 and seals the textile lining 2 from the
outside. The second bromobutyl sublayer 27 that is colored
with carbon is visible over the first bromobutyl sublayer
26.
It is clear to the person skilled in the art that the
above-described exemplary embodiment is to be understood as
an example and that the invention is not limited to this,
but can be varied in numerous ways without going beyond the
scope of the invention. It is also clear that the features
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- regardless of whether they are disclosed in the
description, the claims, the figures, or in some other way
- also define individual, essential components of the
invention, even if they are described together with other
features.
