Waterproof shoe

A waterproof shoe structure including at least part of a shoe, has an outer layer, a lining including a functional layer that is waterproof but permeable to water vapor, an insole, and an outsole. The lining containing the functional layer has a lower end area that is turned in and arranged parallel to the outsole, the turned-in end area lies in a common plane with the insole and has an inner edge and an outer edge, the outer edge of the insole runs at least approximately parallel to the inner edge of the turned-in end area, and the insole is joined to the turned-in end area. The outsole is applied by adhesive over a full surface thereof at least to the turned-in end area of the functional layer of the lining, and the lower end of the upper layer is arranged substantially perpendicular to the outsole and at least in a shank area thereof is joined to a retainer arranged parallel to the outsole, and/or at least in a toe area thereof a netting of monofilaments is joined to the lower end of the outer layer. The lining inside the outer layer is arranged in a detached manner.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates to a waterproof shoe structure comprising at least a 
part of a shoe and having an outer layer (1), a lining (2) with a 
functional layer that is waterproof but permeable to water vapor, an 
insole (3), and an adhesive-applied outsole. 
2. Description of Related Art 
A shoe with such a structure is described in the unpublished German patent 
application with reference number 195 13 413.3-26. This shoe is 
manufactured in an adhesive lasting process and serves to increase wearer 
comfort. With this type of shoe it is recommended to affix outsoles with 
adhesive and as well to apply them by injection molding. 
In the past, the development of waterproof shoes whose comfort is increased 
by a functional layer that is waterproof but permeable to water vapor, and 
that as a rule is integrated into the lining layer, was mainly one in 
connection with shoes having an outsole that is produced by injection 
molding, because the molding material used in the production of the 
outsoles guaranteed of its own accord good watertightness from underneath 
and allowed a good bond with the outer material. 
A shoe with injection molded outsole is known from EP-A-0 544 270 in which 
the lower end of the lining is turned in and arranged parallel to the 
outsole. The outer edge of the insole is sewn to the terminating edge of 
the lining. A sole is molded onto this structure. To ensure shape 
stability during manufacture, the lining in the lower area is glued to the 
outer layer. This design cannot be readily applied to shoes with 
adhesive-applied sole, since the forces required to apply the sole are 
considerably greater than when injection molding an outsole, and the 
lining is therefore subjected to considerable stress, possibly leading to 
tears in the waterproof, water-vapor permeable functional layer in the 
lining and to leakage. 
SUMMARY OF THE INVENTION 
The object of the present invention is to provide an additional waterproof 
shoe structure with an adhesive-applied outsole, which structure is not 
manufactured only as an adhesive lasting process. In particular, the 
invention has the objective of providing a shoe structure in a sewn style 
(Strobel process) that can be fitted with an adhesive-applied outsole.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
The object of the invention is satisfied by a waterproof shoe structure 
comprising at least a part of a shoe, having an outer layer, a lining with 
a functional layer that is waterproof but permeable to water vapor, an 
insole, and an outsole, whereby the lining containing the functional layer 
has a lower end area that is turned in and arranged parallel to the 
outsole, the turned-in end area lies in a common plane with the insole and 
has an inner edge, the outer edge of the insole runs at least 
approximately parallel to the inner edge of the turned-in end area, and 
the insole is joined to the turned-in end area, the structure being 
characterized in that the outsole is applied by adhesive over the surface 
at least to the turned-in end area of the functional layer of the lining, 
the lower end of the upper layer is arranged substantially perpendicular 
to the outsole and at least in the shank area is joined to a retainer 
arranged parallel to the outsole and/or at least in the toe area a netting 
of monofilaments is joined to the lower end of the outer layer, and that 
the lining inside the outer layer is arranged in a detached manner. 
As noted, the lower end area should be in a plane with the insole. This 
means that the lower end area of the lining and the insole should be 
arranged in such a way that both the end area of the lining and the insole 
lie flat on the outsole. This does not rule out, however, that the insole 
and the lower end area of the lining might overlap. But there can readily 
be a separation between the inner edge of the end area of the lining and 
the outer edge of the insole. In this case, the insole is preferably sewn 
to the turned-in end area of the lining (Strobel process). In sewing these 
two parts, a separation can readily be bridged by the threads forming the 
seam. 
An essential element of the present invention is that the adhesive used to 
affix the outsole creates a waterproof bridge between the functional layer 
and the outsole. This can be achieved by using a very thin layer of 
adhesive so that an intimate bond is achieved between the outsole and the 
functional layer. A thicker adhesive layer can also be used, but adhesives 
are then preferably employed that are waterproof after setting. In this 
case, polyurethane adhesives are excellently suited. 
It is also advantageous if, at least in the toe area, a netting of 
monofilaments is joined to the lower end of the outer layer, preferably by 
sewing, and the shape of the toe area of the outer layer is thereby 
stabilized. 
In the shoe structure of the invention, a direct connection between the 
lining and the outer layer, for example gluing the lining to the outer 
layer, can be dispensed with completely. In other words: the lining inside 
the outer layer is arranged in a detached manner or is joined only to the 
upper edge of the outer material, i.e., the edge facing away from the sole 
and representing the opening for inserting the foot. 
The dimensional stability of the shoe structure during the manufacturing 
process can also be improved by joining, preferably by sewing and at least 
in the shank area, a netting of monofilaments to the lower ends of the 
outer layer, thus stabilizing the shape of the outer layer. This netting 
can, however, also extend over the entire foot area if precise retention 
of the shape of the shoe structure is required, for example. 
To provide dimensional stability during the manufacturing process, it has 
also proven favorable to extend the outer layer downward in the toe area 
and then turn it in, so that the turned-in part of the outer layer is 
arranged parallel to the outsole. In this connection it is advantageous if 
a wedge is cut out directly at the tip and the edges thus produced are 
sewn together. This method of stabilizing the shape is also described in 
the yet unpublished German patent application with reference number 195 13 
412.5 for shoes with injection molded sole. 
In the heel area as well, it has proven advantageous to extend the outer 
layer in the heel area downward and to turn it in such a way that the 
turned-in part of the outer layer is arranged parallel to the outsole. In 
this case, it has proven beneficial if, in the area where the outer layer 
is turned in, the outer contour of insole abuts the functional layer, and 
the outer layer, together with the functional layer, is turned over the 
outer contour of the insole. perpendicular to the outsole and join it, at 
least in the area of the shank, to a retainer that is parallel to the 
insole. 
It is also advantageous if, at least in the toe area, a netting of 
monofilaments is joined to the lower end of the outer layer, preferably by 
sewing, and the shape of the toe area of the outer layer is thereby 
stabilized. 
At least the two latter embodiments allow dispensing with any direct 
connection between the lining and the outer layer, for example gluing the 
lining to the outer layer. In other words: the lining inside the outer 
layer is arranged in a detached manner or is joined only to the upper edge 
of the outer material, i.e., the edge facing away from the sole and 
representing the opening for inserting the foot. 
The dimensional stability of the shoe structure during the manufacturing 
process can also be improved by joining, preferably by sewing and at least 
in the shank area, a netting of monofilaments to the lower ends of the 
outer layer, thus stabilizing the shape of the outer layer. This netting 
can, however, also extend over the entire foot area if precise retention 
of the shape of the shoe structure is required, for example. 
To provide dimensional stability during the manufacturing process, it has 
also proven favorable to extend the outer layer downward in the toe area 
and then turn it in, so that the turned-in part of the outer layer is 
arranged parallel to the outsole. In this connection it is advantageous if 
a wedge is cut out directly at the tip and the edges thus produced are 
sewn together. This method of stabilizing the shape is also described in 
the yet unpublished German patent application with reference number 195 13 
412.5 for shoes with injection molded sole. 
In the heel area as well, it has proven advantageous to extend the outer 
layer in the heel area downward and to turn it in such a way that the 
turned-in part of the outer layer is arranged parallel to the outsole. In 
this case, it has proven beneficial if, in the area where the outer layer 
is turned in, the outer contour of insole abuts the functional layer, and 
the outer layer, together with the functional layer, is turned over the 
outer contour of the insole. 
Shape stabilization can also be ensured by forming the lower end area of 
the outer layer as a drawstring passage. This can be accomplished by 
turning back the lower end area and joining it to the outer layer, and 
inserting into the resulting passage a cord by which the lower end of the 
outer layer is held. In this connection it has proven quite advantageous 
if the drawstring passage is arranged in the toe area of the shoe 
structure and extends approximately to the shank area of the shoe 
structure and if the free ends of the drawstring cord in the shank area 
are directed inward and parallel to the outsole and joined together. 
It is of particular benefit for the cord to be a monofilament, because the 
cord can then be completely enveloped by the adhesive. If multifilament 
threads are used for the cord, some embodiments involve the risk that 
water can penetrate to the insole via capillary action in the cord. 
As mentioned previously, it is especially advantageous to bond the outsole 
to the functional layer using a waterproof adhesive. If a material is 
chosen for the outsole which is not completely waterproof, such as 
leather, it is recommended to also glue the insole to the outsole using a 
waterproof adhesive in order to provide a barrier layer and thus 
counteract possible penetration of water via the outsole. 
The waterproof shoe structure in accordance with the invention preferably 
exhibits a lining that is a laminate, in which a lining layer is joined to 
the functional layer. A membrane marketed under the trademark SYMPATEX has 
proven quite successful as a functional layer. 
In special cases, it can be of advantage to have the side of the functional 
layer facing away from the lining layer joined to a textile reinforcing 
layer and to carry out the adhesive application of the outsole to the end 
area of the functional layer in such a manner that the textile reinforcing 
layer is completely embedded in the layer of adhesive necessary for 
bonding. In this connection, it is important that the layer of adhesive 
completely envelop the threads of the textile reinforcing layer to ensure 
a waterproof barrier from the outside. In particular, monofilaments should 
also be used for the textile reinforcing layer to effectively prevent the 
seepage of water caused by capillary action, as is often observed in the 
case of multifilament yarns. 
In this connection it is especially beneficial if the adhesive bonding the 
outsole to the functional layer also includes the inner edge of the 
turned-in end area of the functional layer. In the case in which the 
adhesive does not completely penetrate the textile fabric of the lining 
arranged toward the sole, but does include the inner edge of the turned-in 
end area of the lining, the adhesive can effect an intimate bond with the 
functional layer at the latter locations, because this functional layer is 
easily accessible at the edge. 
In FIGS. 1 and 2, the outer layer is indicated by 1. Within the outer layer 
1 is a lining 2, the lower area of which is turned in, and the inner edge 
of this turned-in end area extends up to seam 4. Seam 4 joins the lower 
end area of lining 2 with an insole 3, whose outer edge also is located in 
the area of seam 4. The heel area is reinforced by means of a counter 5. 
In the shank area there is a monofilament netting 6 that is sewn to the 
outer layer 1 via seam 7. Likewise, in the toe area a netting 8 is sewn to 
the outer layer 1 via a seam, not shown. In accordance with the invention, 
lining 2 consists of a laminate which has on the foot side a lining layer 
and on the sole side a functional layer to which the sole, not shown, is 
affixed. The essential point is that the adhesive provides full-surface 
contact between the sole and the functional layer to prevent water from 
seeping in from the outside toward insole 3. As a rule, insole 3 is 
affixed to the outsole as well. This is recommended in any case if a 
material is chosen for the sole that absorbs water over time, as is the 
case with non-impregnated leather, for example. It is also an advantage if 
the lining has a textile reinforcing layer on the side of the functional 
layer that is not in contact with the foot. 
FIG. 3 shows a further embodiment of the shoe of the invention in which the 
components that are identical to the embodiment shown in FIGS. 1 and 2 are 
indicated by identical numbers. These components will not be described 
again. In this embodiment the outer layer in the toe area is turned in 
(area 9). Directly at the tip, a wedge has been cut out of the outer 
layer. The edges of the outer layer resulting from cutting out the wedge 
are joined together by a seam 10. In area 9 of outer layer 1, which is 
turned in, additional wedges can be cut out, and, again, all resulting 
edges must be joined by seams. In the lower end area of the lining as 
well, it is advisable in all areas where the shoe has a relatively small 
radius, as is the case in the toe and heel areas, to cut into the 
turned-in lining and to join the resulting edges in a waterproof manner. 
This waterproof joint can be achieved, for example, by affixing with 
adhesive. It is also possible to sew the edges created by cutting out a 
wedge, but the seam must then be made watertight in an effective manner. 
This can, for example, be achieved using a waterproof tape which 
completely covers the area of the seam. The watertightness of such seams 
must at least be guaranteed on the side of the lower end area of the 
functional layer that faces the outsole, so that a perfect seal is 
achieved. 
FIGS. 4 and 5 show a further embodiment of the shoe in accordance with the 
invention, and, again, components identical to FIGS. 1 to 3 are referred 
to by identical numbers. The lower end of outer layer 1 is formed into a 
drawstring passage 12, also referred to as a tunnel, in which a cord 11 is 
inserted. Drawstring passage 12 reaches from the toe area to the shank 
area of the shoe, where both ends of the cord emerge from the passage and 
are tied in a knot. 
FIG. 6 shows the bottom view of a shoe, the front part of which is provided 
with a shoe structure in accordance with the invention, while the rear 
part, i.e., the part of the shoe toward the heel, is manufactured in an 
adhesive lasting process. For this purpose, outer layer 1 in the heel area 
is extended downward and turned in such a way that the turned-in part 1' 
of outer layer 1 is oriented parallel to the outsole. In the region where 
outer layer 1 is turned in, the outer contour of insole 13 abuts the 
functional layer 2 (contour insole). Together with the functional layer 2, 
outer layer 1 is turned over the outer contour of insole 13. In this 
connection, the two parts of the insole, parts 3 and 13, can be 
manufactured as a unit or as two separate pieces. In the latter case the 
two pieces 3 and 13 overlap. FIG. 6 shows the case in which this overlap 
is realized in the area of the retention netting 6. In the illustrated 
embodiment of the shoe structure of the invention, in which the two pieces 
3 and 13 of the insole overlap, the result is an extraordinary high degree 
of flexibility in the overlap region. For this reason, this overlap region 
should be located in the shoe where flexibility is required. 
With the shoe structure in accordance with the invention, it is not 
necessary to have the outer layer glued to the lining. As a rule, it is 
sufficient to have retention netting sewn (by a Strobel process) to the 
outer layer, as previously explained, or to turn in the lower part of the 
outer layer. Even if the lower part of the outer layer is turned in, 
adhesive lasting--gluing to the turned-in end area of the lining--is not 
absolutely necessary, because retention is effected by the adhesive that 
is used to affix the outsole. That is why the shoe structure of the 
invention can be produced particularly economically.