|CLAIMS l. A method for the application of gold and other precious metals on fabrics and the like, characterized in that it comprises the following steps:
- depositing onto the fabric (14) an elastic adhesive (18) of polymeric type in the shape of a desired image;
- depositing onto the adhesive a thin layer (22) of gold or other metal;
- removing the fragments (26) of the thin layer lying outside the contour of the image formed by the adhesive;
- allowing the adhesive to set or dry. 2. The method of claim 1, characterized in that said thin layer is an impalpable leaf of gold or other metal.
3. The method of claim 1, characterized in that said thin layer is a fine powder of gold or other metal strewn onto the adhesive.
4. The method of claim 2, characterized in that, after the adhesive (18) has dried, said steps of depositing the adhesive, depositing the leaf and removing the free fragments are repeated in superposition a desired number of times.
5. The method of claim 4, characterized in that said desired number of times is in the range 1 to 4.
6. The method of any of claims 1 to 5, characterized in that it comprises a final step of depositing said adhesive (18) superposed to said image, as a protection to the metal.
7. The method of any of claims 1 to 6, characterized in that said adhesive (18) is applied by means of a silk screen (10).
8. The method of any of claims 1 to 7, characterized in that said adhesive (18) is a polyurethane-based adhesive.
9. The method of any of claims 1 to 7, characterized in that said adhesive (18) is a polyester-based adhesive.
10. The method of any of claims 2, 4 or 5, characterized in that the impalpable leaf (22) is deposited from a supporting tissue (24). 11. The method of any of claims 2, 4, 5 o 10, characterized in that the impalpable leaf (22) has a thickness of 1 to 10 micron.
This invention is concerned with a method for permanently applying metals, such as gold, platinum and the like, on garments and fabrics in general.
Decorating fabrics with graphical patterns and designs has always had a special importance in the fashion industry. In particular, in relatively recent times a practice has developed of providing garments, particularly T-shirts, skirts, foulards and the like with designs such as logos, text and images, by means of print or silkscreen processes using different kinds of non-watersoluble inks, which have often been emulsified with a plasticizing agent (e.g. plastisol) to maintain flexibility and elasticity in the decorated fabric.
In order to further embellish garments, it is also known to provide them with decorations made of gold or other metals or precious stones. To this end, the only approach has been to sew or incorporate in the fabric trimmings such as paillettes, medals, chains and the like, comprising gold or other precious metal. However, that kind of decoration is quite expensive, because it involves a considerable amount of metal, and can therefore only be adopted for luxury garments, such as are intended for exceptional circumstances. Moreover, such relatively massive decorations reduce the pliability of the fabric and therefore make the garment less comfortable. Last but not least, another drawback is that the garment so adorned badly lends itself to washing, and normally it is necessary that the decorations are removed before washing the garment, only to be subsequently re-attached.
It is the main object of the invention to provide a method for the application of decorations of precious metals, such as gold and the like, on fabrics, so that the decoration is permanent, flexible and fast to all kinds of usage including wearing and washing.
Another object is to provide the above decorations so that they will stand both repeated crumpling and washing of the garment, without deterioration of the decoration or erosion of the metal. Another object is to provide a metal application method such that only very small amounts of metal are required, whereby the manufacturing cost of the fabric is not unduly increased with respect to a fabric that is printed with conventional decorations. The invention achieves the above and other objects and advantages, such as will appear from the following disclosure, by a method for the application of gold and other precious metals on fabrics and leather, having the inventive features recited in claim l. Other accessory features are recited in the dependent claims.
The invention is disclosed in more detail with reference to preferred embodi- ments, shown in the attached schematic drawings, in which the vertical scale, for the sake of clarity, is highly exaggerated with respect to the horizontal scale. In the drawings:
Fig. l is a schematic cross-section view of an initial step in the method of the invention, according to a first embodiment; Fig. 2 is a view similar to Fig. 1, in a subsequent step of the method;
Fig. 3 is a view similar to Fig. 2, in a subsequent step of the method.
In preferred example of implementation of the method, the negative image of the image to be made on the fabric is created on a silkscreen frame 10, by a conventional technique, i.e. by forming obstruction areas 12 to define the boundary of the image. Frame 10 is then placed on the fabric 14 which is to be decorated, and which has been previously laid flat on a workbench 16. Subsequently, as shown on Fig. 1, the fabric is spread with a layer 18 of an elastic adhesive (further described below) through the free lattice 20 of silkscreen 10, in a way known per se.
When the above first pass of adhesive has set, a second pass is preferably applied by the same technique and in the same position on the fabric.
After the second pass has been completed, and before it sets, a thin impalpable leaf of the desired metal (gold, platinum or the like) is deposited on the adhesive. As shown schematically on Fig. 2, the leaf 22 may be deposited by separation from a supporting tissue 24, made of polyethylene or other pliable synthetic material. After the leaf has been applied on the adhesive with the help of the tissue, the tissue is separated by peeling it off, while the metal strongly adheres to the adhesive 18. The excess metal fragments 26, which are free from the adhesive and break off beyond the boundary of the image shape, can be recovered, and the adhesive is allowed to dry or set.
The adhesive chosen for the above procedure is an elastic polimeric adhesive, preferably a polyurethane-based adhesive, with or without solvent, or an adhesive based on polyesters containing aliphatic di-carboxylic acids, such as adipic acid and sebacic acid. Both kinds of glues exhibit a high plasticity and a high elasticity. Both polyurethane-based adhesives and polyester-based adhesives, as well known to persons skilled in the art, are free from isocyanates and fully harmless to health.
The above-described gold or silver leaf preferably has a thickness in the range 1 to 10 μπι, and is typically obtained by a hammering procedure between leather panels, as known in the art. Gold and silver leaves of this type are commercially available for use on rigid supports, in bookbinding and similar applications.
After the adhesive is set and dried, the above procedure is preferably (but not necessarily) identically repeated in order to apply a second, and possibly a third and fourth leaf of the desired metal, superposed to the leaf previously deposited, each time with a drying interval. The number of layers depends on several factors, among which is the thickness of the individual leaf.
After laying the desired number of leaves, a final adhesive layer is preferably spread onto the decoration, through the same silkscreen used in the previous steps (not shown in the drawings), in order to improve the final protection of the decoration, although this step is not mandatory. After this final layer has set and dried, the decorated fabric is complete.
The adhesive's setting and drying times can vary, depending not only on the specific formulation of the adhesive, but also depending on the drying conditions, whether natural or assisted, as either the adhesive may be allowed to set by mere exposure to the air, or, alternatively, the setting or drying may be aided by infrared or sometimes ultraviolet irradiation. The above described decoration may take any shape, similarly to decorations printed with conventional inks.
Surprisingly, the fabric decorated with noble metals as disclosed above maintains all the mechanical properties of non-metallized fabrics, and, in particular, can be folded and crumpled in the metallized area, as well as elastically extended, due to the properties of the adhesive. It is believed that the metal molecules, typically gold, adhere more strongly to the adhesive substrate rather than with one another, and therefore conform to the distortions of the fabric without disgregating. Wash- ability also turns out to be comparable with a conventional printed fabric, without loss or erosion of the metal, due to the impermeability of the adhesive.
Since the metal leaf is extremely thin, the amounts of metal employed are also quite small, and quite small is therefore the additional cost of the complete garment, compared to an equivalent garment, such as a T-shirt, that has been conventionally decorated with known inks and dyes. As an alternative to depositing a thin metal leaf, it is also possible, after the step of applying the adhesive on the fabric, to deposit a layer of very thin metal powder. After setting and removal of the metal powder outside the boundary of the adhesive, furhter applications of adhesive and metal may follow, either in the form of powder or of a leaf, as described above with reference to Figs. 1-3. However, depositing the powder as described above, although possible, is in general more expensive for an equivalent visual impression, because it is unfeasible to insure a complete coverage unless an overall amount of metal is deposited that is larger than the amount contained in an equivalent leaf.
In conclusion, the invention provides fabrics and garments having a high degree of preciousness, without hampering the usability of the garments and without causing undue increases of their sale price with respect to comparable garments bearing conventional printed decorations.