The present invention relates to a process for waterproofing semimanufactured shoes, clothing items and accessories, in particular during their manufacture. The present invention also relates to a device for carrying out the process and the semimanufactured products obtained with the process.
The International application publication No. WO 00/22948 in the name of SAES Getters S.p.A. discloses a process for waterproofing leather and semimanufactured products made up of leather pieces sewed together. This known process comprises a pressing on the inner leather surface of at least one semi-permeable membrane whose surface contacting the leather is provided with a glue pattern. With this arrangement a suitable transpiration of the leather is obtained even in the areas where it is glued to the membrane.
However, this known process cannot be applied to semimanufactured products made of leather or fabric, also joined with other materials, which cannot be completely stretched onto a table since they have already taken, during the manufacture, a three-dimensional conformation with at least one inner surface and one outer surface. A typical example of the semimanufactured products is shoe uppers considered in their final working step, before the application of an inner lining, if any. In this step it is not possible any more to stretch the shoe upper onto a table without overlapping portions of the shoe upper itself, with consequent permanent deterioration of the shoe upper, if pressed. Other semimanufactured products of this kind can be shoe uppers of boots, gloves, hats and any kind of clothing items during their final manufacturing step.
It is therefore an object of the present invention to provide a waterproofing process free from the disadvantages, i.e. a process which can be applied in a suitable manner even to semimanufactured products having a three-dimensional conformation. The object is achieved with a process for waterproofing a semimanufactured product, particularly shoes, clothing items and accessories, the semimanufactured product having a three-dimensional conformation, at least one inner surface and one outer surface, characterized in that it comprises the following operative steps:
turning inside out the semimanufactured product so that its inner surface is turned outwards;
inserting at least one shaped member inside the semimanufactured product;
pressing the semimanufactured product provided with the shaped member between at least a pair of sheets of a semi-permeable membrane whose surface turned toward the semimanufactured product turned inside out is provided with a glue pattern; and
turning the semimanufactured product so that its inner surface is turned inwards.
Thanks to the turning inside out and to the shaped member which is inserted before the pressing into the semimanufactured product, it is possible to waterproof the latter also if it is already provided with a three-dimensional conformation. With this arrangement, the semi-permeable membranes, when pressed, can perfectly adhere to the surfaces of the semimanufactured product without any formation of pleats or wrinkles.
Furthermore, the semi-permeable membranes, if they extend beyond the semimanufactured product folded and flattened, can adhere to each other and form at least two strips that seal the semimanufactured product during the pressing. With this arrangement, the semimanufactured product is perfectly waterproofed on its whole surface.
Another advantage of the process according to the present invention lies in the fact of being carried out in a simple and quick way without particularly complex and expensive machines, so that it can be employed not only in industrial production, but also in handicraft production, in particular of shoes.
According to a particular aspect of the invention, the process can be carried out in a simple and effective way by a particular device comprising a pair of deformable pressing plates.
The foregoing summary, as well as the following detailed description of preferred embodiments of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:
Referring to
Referring to
In the present embodiment the glue pattern is made up of a plurality of dots of polyurethane glue, having a diameter comprised between 0.1 mm and 0.8 mm and a density comprised between 50 dots/cm2 and 200 dots/cm2. In other embodiments of the present invention the glue pattern may be made up of glue arranged according to dot matrixes or along mutually parallel and/or perpendicular lines. By heating the membranes 5 during the pressing, their perfect adhesion to the shoe upper 1 is obtained, without the risk of plugging the pores thereof with the glue. Membranes 5 are suitably made up of a sheet of a semi-permeable material, for instance made of polyurethane, polytetrafluoroethylene, polyester or other polymers, the thickness of which is preferably comprised between 5 μm and 100 μm. Particularly, membranes 5 according to the present embodiment of the invention are made of polyurethane. Further, they are preferably elastic, with a coefficient of elongation higher than 50%, particularly 100%, and they are not porous, since they carry out the water vapor passage by osmosis, and therefore, differently from the porous membranes, the water passage is prevented even when they are pulled or bent. Further information about membranes 5 is contained in the International application publication No. WO 00/22948 in the name of SAES Getters S.p.A.
The surface of the semi-permeable membranes 5 which is not provided with the glue pattern is generally fastened to a support sheet (not shown in the Figures) which avoids its possible accidental breakage or bending before the application. The sheet can be made of paper and can be detachable after that membranes 5 have been adhered to the shoe upper 1. In other embodiments of the present invention, the support sheet can be made of different materials, for example fabric or a similar material, and be firmly fastened to membranes 5, if it is desired that the shoe upper 1 is internally lined at the end of the processing.
Referring to
Once extracted from the press and cooled, the shoe upper 1 waterproofed with the membranes 5 can be separated from the shaped member 4 and turned for returning to the original conformation. The shaped member 4 can be further reused for the lamination of other shoe uppers having the same shape and the same size.
Referring now to
As in the first embodiment, the shoe upper 1 turned inside out and internally provided with the shaped member 8 is arranged like a sandwich between at least one pair of sheets 5 of a semi-permeable membrane provided with at least one glue pattern. However, in this second embodiment the whole of the shoe upper 1 and of the semi-permeable membranes 5 is pressed by a particular device according to the present invention, which comprises a press provided with a pair of deformable plates 10.
With reference to
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In
Changes and/or additions can be made by those skilled in the art to the hereinabove described and illustrated embodiments, while remaining within the scope of the invention itself. It is for instance obvious that, by suitably modifying the shape of the shaped member 4 or 8, it is possible to waterproof not only the shoe uppers, but also gloves, hats and any kind of clothing items, which may be made not only of leather, but also of fabric and/or of other materials.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.
Number | Date | Country | Kind |
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MI2000A 001839 | Aug 2000 | IT | national |
This application is a divisional of U.S. patent application Ser. No. 10/358,465, filed Feb. 5, 2003, which was a continuation of International Patent Application No. PCT/IT01/00424, filed Jul. 31, 2001, published in the English language on Feb. 14, 2002, under International Publication No. WO 02/11571, and the disclosures of which are incorporated herein by reference.
Number | Date | Country | |
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Parent | 10358465 | Feb 2003 | US |
Child | 11971286 | US |
Number | Date | Country | |
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Parent | PCT/IT01/00424 | Jul 2001 | US |
Child | 10358465 | US |