EP4092140A1

EP4092140A1 - Method of decorating an exotic leather

Info

Publication number: EP4092140A1
Application number: EP22173467.6A
Authority: EP
Inventors: Elena Lodi
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-05-18
Filing date: 2022-05-16
Publication date: 2022-11-23
Anticipated expiration: 2042-05-16
Also published as: EP4092140B1; EP4092140C0; IT202100012848A1

Abstract

Method for decorating an exotic leather (1), comprising the steps of preparing an exotic leather (1) in a semi-finished state, that is to say tanned but not finished, tanning the exotic leather (1) with chromium in such a way that the percentage of chromium present in the exotic leather (1) in the semi-finished state is between 6% and 10% and decorating the exotic leather (1) in the semi-finished state by tattooing with water-based acrylic colours.

Description

The present invention relates to a method for decorating an exotic leather and an exotic leather decorated according to the proposed method. The sector of reference is the tanning industry, specifically the production of artworks on exotic leathers or objects made from exotic leathers. Exotic leathers here means leathers from exotic animals, such as alligators, crocodiles, caimans, lizards, ostriches, pythons and the like.
Various techniques for decorating leathers are known. In particular, there exist industrial techniques such as laser or digital printing or artisanal techniques such as painting with a brush or the tattooing technique. Document ITRN20000038 A1 shows a process for indelibly decorating natural tanned leather and equivalent synthetic leather, which comprises a step of positioning a perforation element in a predetermined point of a leather; a step of only partially perforating the thickness of the leather by means of the perforation element; repeating in sequence the positioning and perforating steps, with the production of holes in a predetermined number and position according to a defined design, until forming overall at least part of a precise, planned decoration.
Document WO2020/173532 A2 describes a method of manufacturing footwear that comprises the following steps: - providing a leather base layer - providing a leather attachment layer, - fixing the leather base layer and the leather attachment layer with an intermediate application of adhesive between them, - activating the applied adhesive - forcing the leather base layer and the leather attachment layer against each other under pressure with the adhesive between them - curing the adhesive and thereby bonding the leather base layer and the leather attachment layer to each other, and - integrating the bonded leather base layer and the leather attachment layer as part of the footwear.
Document ITRM20080107 A1 proposes a method for producing a decoration on tanned leather or the like, comprising the steps of: (a) providing a portion of tanned leather or the like, said portion of leather having an aesthetic surface, said aesthetic surface having already been subjected to a polishing operation; and (b) making a plurality of perforations on said aesthetic surface and injecting a coloured substance into each of said perforations.
In this context, techniques of tattooing on calfskin leathers using pigments are known. For example, document EP1570092 shows a preliminary treatment of applying a solvent and a subsequent step of actually decorating the leather.
However, a solution of this type is not applicable effectively and to the customer's satisfaction on exotic leathers, since the latter have peculiar, very distinctive characteristics compared to calfskin leathers or the like. Exotic leathers are characterised by irregular surfaces (for example, scaly surfaces are present in the case of crocodile leathers), which impede the application of pigments as described in the above-cited patent. Furthermore, the application of a solvent on an exotic leather would not only not help the subsequent decorating step, but would also result in aesthetic damage to the exotic leather, which would cause its rejection.
At the time of writing there do not exist any techniques for decorating exotic leathers by tattooing that enable an effective, faithful decoration, to the customer's full satisfaction.
In this context, the technical task at the basis of the present invention is to propose a method for decorating an exotic leather and a decorated exotic leather that overcome the above-mentioned drawbacks of the prior art.
In particular, the object of the present invention is to propose a method for decorating an exotic leather that assures an optimal and faithful decoration also in the case of irregular leather surfaces. Another object of the present invention is to provide a method for decorating an exotic leather that allows an optimal absorption of colour by the exotic leather.
A further object of the present invention is to propose a method for decorating an exotic leather that allows a regular between-scale and inter-scale absorption and the production of a faithful decoration.
The stated technical task and specified objects are substantially achieved by a method for decorating an exotic leather comprising the steps disclosed in one or more of the appended claims.
Additional features and advantages of the present invention will emerge more clearly from the approximate and hence non-limiting description of a preferred but not exclusive embodiment of a method for decorating an exotic leather and a decorated exotic leather, as illustrated in the appended drawings, in which:

figure 1 illustrates a schematic perspective view of an exotic leather on which a decoration is produced according to the present invention;
figure 2 illustrates an experimental test, illustrated in black and white, of a decoration on exotic leather produced by the Applicant according to the present invention.

With reference to the figures, the number 1 indicates an exotic leather. As illustrated in figure 1, the exotic leather 1 referred to is a product in its own right. Alternatively, the decoration may take place on an exotic leather of an object.
The method comprises a step of preparing an exotic leather 1 in a semi-finished state. In other words, the exotic leather 1 is of the unfinished tanned type. In the tanning industry, this type of semi-finished product is known by the name of "crust" leather. This semi-finished state refers to a leather that has been tanned and dried, but not coloured.
The step of preparing an exotic leather 1 in a semi-finished state comprises a step of tanning the exotic leather 1 with chromium. This step is carried out in such a way that the exotic leather 1 in a semi-finished state contains a percentage of chromium comprised in the range of 6%-10%.
Once an exotic leather 1 has been prepared as described above, the method comprises a step of decorating the exotic leather 1 in a semi-finished state by tattooing with water-based acrylic colours.
By way of example, a list of water-based acrylic colours used during the experimental production of a decoration (clown's face, illustrated in figure 2) on alligator leather in the "crust" state is given below:

powder pink 0.5 mL
cerulean blue 2.5 mL
titanium white 10 mL
cadmium yellow 3.5 mL
vermilion 0.3 mL
Saturn yellow 0.2 mL
Mars black 0.5 mL
lamp black 0.3 mL
cobalt turquoise 0.5 mL
Chinese white 10 mL
cadmium yellow medium 0.2 mL

The colours are then blended together to obtain different shades and tones.
The technique of tattooing on leather is of a known type and will not be further described. It is possible to make reference, for example, to the technique described in the above-cited EP1570092 .
The method preferably comprises a step of mixing the water-based acrylic colours with resin in percentages ranging from 3% to 70%. The percentage will depend on the degree of brightness desired for the final product.
The step of decorating the exotic leather 1 preferably takes place by means of an apparatus for tattooing on human skin of a known type. In this manner it will be possible to speed up the tattooing operations compared to painting by hand. Furthermore, the use of machinery already known for the tattooing technique enables the method to be easily exploited.
The method preferably comprises a step of applying a water-based fixative. This operation takes place during or after the step of decorating the exotic leather 1. The operation preferably takes place after the decoration of the leather so as to allow time for the colours to dry.
The water-based fixative serves to protect the decoration from aging and/or from any atmospheric agents which would impair the work.
In particular, it is worth underscoring that the exotic leather 1 is not subjected to dyeing before being decorated. Similarly, the exotic leather 1 is not treated with a solvent.
The present invention also relates to an exotic leather comprising one or more decorations obtained according to the method proposed above.
The features of the method for decorating an exotic leather and of the decorated exotic leather according to the present invention appear clear from the above description, as do the advantages thereof.
In particular, the use of unfinished or "crust" leathers tanned with a range of percentages of chromium specifically intended for exotic leathers has proven to be fundamental for the successful execution of the decoration. Furthermore, the use of water-based acrylic colours in combination with semi-finished chrome-tanned leathers enables an optimal result to be obtained, with the effect of producing accurate decorative works, in a precise, controlled manner, also on irregular and/or scaly leathers like exotic leathers.

Claims

Method for decorating an exotic leather (1), comprising the steps of:
preparing an exotic leather (1) in a semi-finished state, that is to say tanned but not finished, said step of arranging an exotic leather (1) in a semi-finished state comprising the step of tanning the exotic leather (1) with chromium in such a way that the percentage of chromium present in the leather is between 6% and 10%;

decorating the exotic leather (1) in the semi-finished state by tattooing with water-based acrylic colours.
Method according to claim 1, comprising a step of mixing the water-based acrylic with resin in percentages varying from 3% to 70% depending on the desired degree of brightness, said step of mixing taking place before the step of decorating the exotic leather (1).
Method according to claim 1 or 2, wherein the step of decorating the exotic leather (1) takes place by means of an apparatus for tattooing on human skin.
Method according to any one of the preceding claims, comprising the step of applying a water-based fixative on the decoration produced so as to protect it from aging and/or from atmospheric agents, said step of applying a water-based fixative taking place at least partially together with or after the step of decorating the exotic leather (1).
Method according to any one of the preceding claims, wherein between the step of preparing an exotic leather (1) in a semi-finished state and the step of decorating the exotic leather (1), the exotic leather (1) does not undergo any colouring treatment.
Exotic leather (1) comprising one or more decorations produced by means of a method for decorating according to any one of the preceding claims.