Artificial leather-like coated support

The present invention relates to an artificial leather-like coated support.

More in detail, the invention relates to a coated support of the kind known as artificial leather, having improved features of elasticity and workability and at the same time of resistance to wear and tear, made of two or more layers of fabric or nonwoven fabric coated by one or more coating layers of plastic material and interspersed with one or more interaveragete layers of the same or a different plastic material, obtained through the production, directly on a paper buttering line for the production of artificial leather.

The invention belongs to the field of the production of artificial leather (also known as "fake leather" or synthetic leather, made on a paper buttering line, from now on simply called artificial leather).

It is known that the production of artificial leather-like coated supports is characterised essentially by the buttering of one or more coating layers of polymeric material (generally polyurethane or polyamide) of paper and by the subsequent coupling of a support layer with said coating layer, obtained by buttering of said support layer on said coating layer. The thus obtained multi-layered structure is then passed through oven for firing. The result of the working process, shown with reference to figure 1 , is a composite materia) having a coating layer 11 of a plastic material on one side, simulating the leather surface, and a support 12 on the other side, in the example made of a fabric of the kind of jersey, the yarns of the knitting being shown in section and being referred to with the numeral 13.

The coating layer 11 of a plastic material is generally made of polymers, resins in emulsion, plasticizers, additives and dyes: in the following in the present description, such plastic material will be referred to with the expression polymeric material, without this leading to a limitation of the nature of the material.

More in particular, according to the prior art, the process of production of artificial leather comprises the following steps: a mixture of polymeric material is cold buttered, for example by means of a doctor, on a support of liner. The nature of the paper support determines the aesthetic aspect of the finished product, because, depending on the kind of paper which is used, the synthetic leather that is obtained at the end of the process has a different surface: perfectly smooth, or patterned in different ways. After one or two subsequent butterings of the mixture on the paper support, during the third buttering a support is coupled which can be a fabric (cotton, polyester), or a nonwoven fabric or jersey. At the end of the process, the paper support is detached to be reused in further working cycles.

Depending on the desired finished product, the coating layer of buttered polymeric material is subjected to additional working steps (such as embossing by engraving and printing by wash effect finish and gloss), only needed to obtain determined aesthaetic results.

For the quality of the finished product, the jersey is the most suitable support, since it allows for a higher transpiration. The raw material is constituted by a mixed fabric of cotton and polyester, worked under a process in continuous: first it is impregnated in a bath of chemical component as plasticizers (polyurethane) diluted with solvents, then it passes in a fixing liquid, then in a system made of rolls giving it the desired thickness (usually about one millimetre); at last it is dried in oven.

As it is well known, at present, making a coating layer of polymeric material buttered with a single support, the artificial leather that it is possible to obtain has parameters such as characteristics of the support (defined by the sub-parameters of weave and fibre kind) and mass per unit area (respectively defined for the support, the coating layer of polymeric material and as a whole for the coated support) being a compromise of different needs. In order to obtain a high elasticity and workability, it is needed, according to the prior art, realizing a a product with a lower thickness (involving a reduction of the product's whole cost), determining on the other side a lower resistance to wear and tear. On the other hand, in order to obtain a product having higher characteristics of resistance to wear and tear, it is needed a higher thickness (involving an increase of the product's whole cost), determining on the other hand a lower elasticity and a worse easiness of working.

In vew of the above, it is evident the need for an artificial leather having at the same time the characteristics of high elasticity, low thickness, high resistance and flexibility and higher softness, maintainin the same thickness.

In this context is presented the solution according to the present invention, which has the aim of providing, through a single productive process, a coated support of the kind multi-layered artificial leather, with two or more layers of buttered polymeric material and two or more supports, in particular a coating layer, two or more supports, and one or more interaveragete layers of polymeric material, interposed between said supports, obtained by intervening in the formulation of the components of polymeric material to butter on and between the supports and in the buttering process, with the aim of compacting the layers of buttered polymeric material and the supports, without jeopardising the resoect of the parameters of characteristics of the product and mass per unit area that would be obtainable instead with a single support.

For example, making again reference to figure 1 , according to the prior art, an artificial leather has features that in the best cases are the following:

- a coating layer 11 of polymeric material (possibly composed of different layers of a same polymeric material or of different superimposed polymeric materials) or polymeric coating having a mass per unit area equal to 320±25g/m ²

- a support layer 12 having a mass per unit area equal to 140±10g/m ²

As a whole, the product obtained is a coated support having a mass per unit area equal to 460±35g/m ² and a thickness equal to 0,65±0,05mm.

The present invention aims at obtaining a coated support of the kind of multi-layered artificial leather having the following minimal characteristics: - a coating layer of polymeric material (in case composed of different layers of a same polymeric material or of different superimposed polymeric materials) or polymeric coating having a mass per unit area equal to 160±12g/m ²

- a first support layer having a mass per unit area equal to 70±5g/m ²

- an interaveragete layer of polymeric material (in case composed of different layers of a same polymeric material or of different superimposed polymeric materials) having a mass per unit area equal to 160±12g/m ²

- a second support layer having a mass per unit area equal to

70±5g/m ²

As a whole, the product obtained is a coated support having a mass per unit area equal to 460±35g/m ² and a thickness equal to 0,65±0,05mm.

These and other results are obtained according to the present invention proposing an artificial leather-like coated support with different layers having the same thickness and higher chemical-physical characteristics with respect to the present artificial leather, which is obtained with a single support, and further a process for the production thereof, providing for the compression of two or more supports imbued in the layers of buttered polymeric material.

Purpose of the present invention is therefore that of realising an artificial leather-like coated support allowing for overcoming the limits of the artificial leather according to the prior art and for obtaining the previously described technical results.

Additional aim of the invention is that said artificial leather can be realized with costs substantially low, as far as both production costs and maintenance code is concerned.

Not last aim of the invention is that of providing an artificial leather that is substantially simple to be used, safe and relyable.

It is therefore a first specific object of the present invention an artificial leather-like coated support, made of a coating layer of a plastic material and of a plurality of support layers made of fabric, nonwoven fabric or jersey, wherein said support layers are imbued in said coating layer.

According to the invention said support layers are interspersed with interaveragete layers of a plastic material, said support layers being imbued in said interaveragete layers.

Preferably, according to the invention, said interaveragete layers are made of a plurality of superimposed substrates of a same plastic material or of different plastic material.

Additionally, said coating layer is made of a plurality of superimposed substrates of a same plastic material or of different plastic material.

Again, according to the invention, said plastic material comprises polymers and/or resins, together with plasticizers, additives, dyes.

Additionally, according to the invention, said support layers are all the same or are different from each other.

Again, said support layers are imbued with each other.

It is therefore a second specific object of the invention a process of manufacturing an artificial leather-like coated support as previously defined, comprising the following steps:

- buttering on a release layer of aa first mixture of plastic materials;

- drying in oven said mixture, forming a coating layer coupled with one release layer;

- buttering on said coating layer of at least a second mixture of plastic materials, equal to or different from that of the first step;

- coupling of two or more support layers made of fabric, nonwoven fabric or jersey with said at least a second buttered mixture, making them imbue in said second buttered mixture, obtaining a multilayered product;

- drying in oven said multilayered product; and

- cooling of said multilayered product.

Preferably, said step of coupling of two or more support layers provides for the buttering of interaveragete layers of a plastic material.

Still more preferably, said buttering step of interaveragete layers of a plastic material provides for one or more iterations of the following steps:

- drying in oven said multilayered product; and - cooling of said multilayered product.

It is evident the efficacy of the artificial leather-like material of the present invention, allowing for achieving the following advantages:

- high elasticity;

- high workability;

- lower thickness;

- high resistence to tear;

- high resistence to wear;

- high flexibility;

- higher softness;

- higher resistance to the detachment of the coating from the support;

- lower costs with higher characteristics;

- use of different supports having different working needs and different final characteristic of the product.

It is therefore possible to make an artificial leather-like material with totally new chemical physical characteristics, both in the supports and in the coating and intermidiate layers of buttered polymeric material, changing thickness, weight, components and relative layers as a function of the needs of the final product.

In particular, the present invention allows for realising a single buttering process a compacted buttered product having two or more jerseys, fabrics, supports, etc., wherein the final thickness is lower than that that would result from the algebraic addition of the same single jerseys, fabrics, supports, etc.

The buttered product presents the characteristics of low costs and softness which are typical of the articles produced by buttering at the same time having a thickness, flexibility and resistance to break expressed in kN never achieved before (as can be seen in the tests of the following examples), higher than those obtained with a leather product.

The previous characteristics can be improved further by intervening on the techinics of fixing of the supports (glueing, electro-welding, fusion, thermo-fusione termo-welding, laser, ecc.) that can vary from the union by micro points, till the total integration of the supports, and/or with microholes in order to allow the product for transpiring.

The invention will be disclosed in the following for illustrative, non limitative purposes, with reference in particular to some illustrative examples, and further to the figures of the enclosed drawings, wherein:

- figure 1 shows a transversal sectional schematic view of an artificial leather according to the prior art,

- figure 2 shows a transversal sectional schematic view of an artificial leather according to a first embodiment of the present invention, obtained according to example 1 ,

- figure 3 shows a transversal sectional schematic view of an artificial leather according to a second embodiment of the present invention, obtained according to example 3,

- figure 4 shows a graphic of the values of applied tension and elongation of the specimens of example 2 during the test of resistance to longitudinal break;

- figure 5 shows a graphic of the values of applied tension and elongation of the specimens of example 2 during the test of resistance to transversal break;

- figure 6 shows a graphic of the values of applied tension and elongation of the specimens of example 2 during the test of longitudinal tear;

- figure 7 shows a graphic of the values of applied tension and elongation of the specimens of example 2 during the test of transversal tear;

- figure 8 shows a graphic of the values of applied tension and elongation of the specimens of example 4 during the test of resistance to longitudinal break;

- figure 9 shows a graphic of the values of applied tension and elongation of the specimens of example 4 during the test of resistance to transversal break;

- figure 10 shows a graphic of the values of applied tension and elongation of the specimens of example 4 during the test of longitudinal tear; and

- figure 11 shows a graphic of the values of applied tension and elongation of the specimens of example 4 during the test of transversal tear.

Example 1. Production of an artificial leather product having two support layers

The aim was that of producing a product made of artificial leather having the characteristics reported in the following table 1:

Table 1

The mass per unit area of the coated support is equal to the sum of the mass per unit area respectively of the support and of the polymeric coating.

Using the production technics of artificial leather according to the prior art it is possible to obtain maximum a coated support having a mass per unit area equal to 460±35g/m ² , equal to the algebric sum of the mass per unit area of a single support (140±10g/m ² ) and of the polymeric coating (320±25g/m ² ). All of this maintaining a thickness equal to 0,65±0,05mm, using a single support.

With reference to figure 2, the artificial leather support according to the present invention, even maintaining the same thickness of 0,65±0,05mm is composed by two supports 12, for a total mass per unit area of 140±10g/m ² , imbued in a coating layer 11 of polymeric material with mass per unit area of 320±25g/m ² , obtaining a coated support with mass per unit area equal to 460±35g/m ² , intervening both in the productive cycle and in the formulation of the mixtures.

In particular, in order to obtain an artificial leather-like coated support having the specified characteristics, the following was made.

Some plastisol were prepared by mixing together different products (es. polymers, resins, plasticizers, additives, dyes etc..) in disc turbo mixers by Molteni, and after the mixture was refined in a triple roll mills by Molteni. Then the subsequent process of buttering of the obtained mixture was performed, in order to obtain the coupling of the polymeric material with a paper support, yet during the first steps of the process, lowering the final values both of thickness and weight. In fact, that allows for performing the operation of coupling (addition of a support) different times in the course of the same step of buttering, using one or more cylinders with micro-holes or other coupling or buttering technics.

In order to obtain the product a four heads buttering line by the firm Isotex was used, composed as follows:

- paper uncoiler;

- first buttering bench of a plastic material, which can be used also for coupling one or more supports on the plastic material buttered;

- first group of heating/drying made of a double battery of six thermochannels each being 1 ,5m long, fed with diathermal oil, thermoventilated in continuous, for a total of 9m;

- first group of cooling by water;

- second buttering bench of a plastic material, which can be used also for coupling one or more supports on the plastic material buttered;

- second group of heating/drying made of a double battery of five thermochannels each being 1 ,5m long, fed with diathermal oil, thermoventilated in continuous, for a total of 7,5m;

- second group of cooling by water;

- third buttering bench of a plastic material, which can be used also for coupling one or more supports on the plastic material buttered;

- third group of heating/drying made of a double battery of eight thermochannels each being 1 ,5m long, fed with diathermal oil, thermoventilated in continuous, for a total of 12m; - third group of cooling by water;

- fourth buttering bench of a plastic material, which can be used also for coupling one or more supports on the plastic material buttered;

- fourth group of heating/drying made of a double battery of six thermochannels each being 1 ,5m long, fed with diathermal oil, thermoventilated in continuous, for a total of 9m;

- fourth group of cooling by water;

- paper detachment group and coiling of the finished product;

- paper coiling group.

In order to heat the diathermal oil a thermoboiler was used, model Ciclonic produced by the firm Ing.Bono, of 1500000 Kcal/h, using naphtha- CH ₄ as fuel, heating the diathermal oil up to a temperature of 295°C.

A paper roll of "Embossed Leda" of the firm Favini for PVC was used adjusting the velocity of the production line at about 20m/min.

On the first bench on the paper was buttered by mowing an amount of about 7g/m ² of dried vynil laque composed by a mixture of 80 parts of vynil laque, in particular "LV 4916" by Stahl, and 20 parts of MEK solvent (methylethylketone), previously mixed with a common fast disc mixer for solvents, reticulating in the first group of heating/drying at an starting temperature of about 70°C and at a final temperature of about 90°C.

After cooling the interaveragete product made of paper coated with a plastic material in a group of cooling by water, on the second buttering bench it was doctor buttered with a thickness of 0,05mm an amount of about 70g/m ² of dried PVC, subsequently gelling the material at a temperature of about 180°C. The mixture after mixing and refining was composed as follows:

- 80kg of Gerphos 430 (Gulec Chemicals);

- 2kg of stabilizer MS 68 (Lagor);

- 18kg of Dinp (Lonza);

- 100kg of resin in emulsion P11 (Ineos);

- 25kg of Martinal ON310 (Omya);

- 10kg of zinc borate (Guleg Chemicals);

- 25kg of Gerphos 2050 (Gulec Chemicals); - 2,5kg of Irgalite Blue BLPO (Ciba);

- 0,5kg of Irgalite Ruby 4BP (Ciba);

- 0,08kg of Cromopatal Violet B (Ciba);

- 0,08kg of Irgalite Green GFNP (Ciba);

- 0,45kg of Irgaplastol Black CM50 (Ciba); e

- 7kg of Titanium Tioxide R-TC30 (Azelis Italia).

After cooling of the paper and the material, on the third buttering bench it was doctor buttered with a thickness of 0,13mm an amount of about 90g/m ² of dried PVC and it was coupled, by making it imbue in PVC, a common polyester jersey with semi-interlock weave of 70g/m ² , subsequently gelling the material at a temperature of about 200°C. The buttered mixture, previously mixed and refined, was composed as follows:

- 80kg of Gerphos 430 (Gulec Chemicals);

- 2kg of stabilizer MS 68 (Lagor);

- 18kg of Dinp (Lonza);

- 100kg of resin in emulsion P11 (Ineos);

- 25kg of Martinal ON310 (Omya);

- 10kg of zinc borate (Guleg Chemicals);

- 25kg of Gerphos 2050 (Gulec Chemicals);

- 2,4kg of Irgalite Blue BLPO (Ciba);

- 0,5kg of Irgalite Ruby 4BP (Ciba);

- 0,08kg of Cromopatal Violet B (Ciba);

- 0,08kg of Irgalite Green GFNP (Ciba);

- 0,45kg of Irgaplastol Black CM50 (Ciba); and

- 7kg of Titanium Tioxide R-TC30 (Azelis Italia).

After cooling the paper and the material, on the fourth bench it was buttered with a micro holed roll of 60mesh an amount of about 165g/m ² of dried PVC and was subsequently coupled with it, a common polyester jersey with semi-interlock weave of 70g/m2 making it imbue in the PVC, subsequently gelling the material at a temperature of about 200°C. The mixture that was buttered, previously mixed and refined, was composed as follows:

- 90kg of Gerphos 430 (Gulec Chemicals); - 2kg of stabilizer MS 68 (Lagor);

- 18kg of Dinp (Lonza);

- 100kg of resin in emulsion P11 (Ineos); e

- 25kg of Magnifin H5 (Omya)

At the end of the working process, after cooling the material, the paper was divided from the finished product.

The finished product was examined and the following characteristics were verified:

- total weight of the finished product with two imbued supports: about 472g/m ²

- thickness: about 0,65mm.

The present example was chosen because it allows to understand at the best the solution proposed according to the present invention, but it is also possibile, obviously modifying the tolerances of the single parameters (support, polymeric coating, coated fabric) further improve the chemical/physical characteristics of the final product. Additionally, it is also possible to add to the same product further support layers equal or different to one another, for example for their composition, weave, type, fibre, needing the same or different glues, polymers, or other products for their coupling and/or the same or different working temperatures. For example, it is possible to work for the composition of a multi-layer with supports needing different working temperatures in order to avoid melting and therefore needing to be processed with different products, putting together in a single finished product the characteristics also different of the different supports, all of this by improving exponentially the final result with low costs.

Example 2. Characterisation of the artificial leather product of example 1

A sampling of artificial leather fabric according to the embodiment disclosed in example 1 was divided into different specimens and subjected to laboratory tests, according to the following norms:

- "UNI EN ISO 1421": Textile supports coated with rubber or plastic materials - Determination of the resistance to break and of the elongation at break";

- "UNI EN ISO 4674-1 Method A": Textile supports coated with rubber or plastic materials - Determination of the resistance to tear";

- "UNI 4818 Parte 7°": Supports coated with polymeric materials - Determination of the percentage elongation under load";

- "UNI 4818 Parte 8°": Supports coated with polymeric materials - Determination of the residal deformation under constant elongation".

Ambient condition during the tests:

- Ambient pressure: 1 atm

- Ambient temperature: 23 ± 1 °C

- Relative umidity: 50 ± 5%

For performing the tests the following devices were used:

- universal machine for material tests INSTRON matr. 091 M1611 equipped with load cell of 5 kN s/n UK 1356 and strainmeters of 50 mm matr. RM 021;

- digital caliber Mitutoyo matr. RM 073

For performing the test of resistance to break were obtained from the specimen of artificial leather fabric according to the embodiment disclosed in example 1 , two series of five fabric specimens, one in longitudinal direction and the othe rin transversal direction, having dimensions 300 ± 1mm x 50 ± 0,5mm.

Each specimen, after an initial conditioning of 24h a 23 ± 2°C and 50 ± 5% of relative umidity, was fixed at the clamps of the dynamometric machine adjusted at a distance of 200 mm, and subjected to tension with a constant velocity equal to 100 mm/min till break.

During the test the values were recorded of applied tension and elongation of the specimen reported in figures 4 and 5 concerning respectively the test of resistance to longitudinal and transversal break. The same data are resumed in the following table 2:

Table 2

Resistance to break

Specimen type specimen n. Maximum load at break (kN)

1 483,8

2 498,3

3 524,5

Longitudinal

4 493,6

5 446,8 average 489,4

1 500,1

2 492,3

3 476,8

Transversal

4 504,1

5 487,3 average 492,1

For performing the test of percentage elongation under load from the specimen of artificial leather fabric according to the embodiment disclosed in example 1 two series of seven specimens of fabric were obtained, one in longitudinal direction and the other in transversal direction, having dimensions 350 x 50mm.

On each specimen, conditioned for 24h a 23 ± 2°C and 50 ± 5% of relative umidity, two reference lines were drawn, positioned at 200mm from one another; the specimens were fixed to the clamps of the dynamometric machine at the distance of the reference signs.

The test was performed subjecting the specimens to tension till reaching an applied load equal to 100N; under these conditions the gauge length was measured and the elongation percentage was calculated. The measured results are reported in the following table 3:

Table 3

Elongation under load (100 N)

Specimen type Specimen n. Elongation (%)

1 21 ,8

Longitudinal

2 20,2 3 19,4

4 20,2

5 20,5

6 19,9

7 19,2 average 20,2

1 31 ,7

2 30,1

3 30,7

4 30,6

Transversal

5 30,2

6 30,8

7 30,0 average 30,6 wherein the percentega elongation was calculated according to the following formula:

A% = 100 (u - y

wherein Li indicates the final length and L ₀ is the initial length (200mm).

In order to perform the test of resistance to tear from the specimen of artificial leather fabric according to the embodiment disclosed in figure 1 , two series of five fabric specimens were obtained, one in longitudinal direction and the other in transversal direction, having dimensions 200mm x 150mm.

Each specimen, from which a tongue was cut measuring 100x50mm, was fixed at the clamps of the dynamometric machine adjusted at a distance of 100mm, so that half tongue is fixed in a clamp and the legs of the specimen are clamped in the other.

Under such conditions the tension was applied, with a velocity of 100 mm/min until the specimen is ripped for 60mm.

During the test the values were recorded of applied tension and elongation of the specimen reported in figures 6 and 7 concerning respectively the longitudinal and transversal tear tests. The same data are resumed in the following table 4:

Table 4

In order to perform the tests of residual deformation under constant elongation from the specimen of artificial leather fabric according to the embodiment disclosed in example 1 two series of seven specimens of fabric were obtained, one in longitudinal direction and the other in transversal direction, having dimensions 350 x 50mm.

On each specimen, conditioned for 24h a 23 ± 2°C and 50 ± 5% of relative umidity, two reference lines were drawn, positioned at 200mm from one another; the specimens were fixed to the clamps of the dynamometric machine at the distance of the reference signs.

Under such conditions tension was applied until an elongation was obtained of 50mm of the gauge length, maintained for 5h; after such period the specimens were freed from the machine and conditioned for 2h at 23 ± 2°C and 50 ± 2% of relative umidity. Finally it was measured the gauge length of the specimens and calculated the elongation percentage. The measured results are reported in the following table 5:

Table 5

Residual deformation after constant elongation (50mm)

wherein the percentage of residual deformation was calculated according to the following formula:

D _R % = 100 (Li - )/(Lu - L ₀ )

wherein Li indicates the final length, L ₀ is the initial length (200mm) and Lu is the length under tension.

Example 3. Production of an artificial leather product having three support layers

The aim was that of producing a product made of artificial leather with the characteristics reported in tables 6.1 and 6.2 as follow:

Table 6.1

Composition Support Jersey polyester 100% Plastic material PVC

Support % >15 <30

Composition%

Plastic material % >70 <85

Table 6.2

The mass per unit area of the coated support is equal to the sum of the mass per unit area respectively of the support and of the polymeric coating.

Example 4. Characterisation of the artificial leather product of example 3

A sampling of artificial leather fabric obtained according to example 3 (schematically shown in figure 3) was divided into different specimens and subjected to laboratory tests, according to the following norms:

- "UNI EN ISO 1421": Textile supports coated with rubber or plastic materials - Determination of the resistance to break and of the elongation at break";

- "UNI EN ISO 4674-1 Method A": Textile supports coated with rubber or plastic materials - Determination of the resistance to tear";

- "UNI 4818 Parte 7°": Supports coated with polymeric materials - Determination of the percentage elongation under load";

- "UNI 4818 Parte 8°": Supports coated with polymeric materials - Determination of the residal deformation under constant elongation".

Ambient condition during the tests:

- Ambient pressure: 1 atm

- Ambient temperature: 22 ± 1 °C

- Relative umidity: 50 ± 5%

For performing the tests the following devices were used:

- universal machine for material tests INSTRON matr. 091M1611 equipped with load cell of 5 kN s/n UK 1356 and strainmeters da 50 mm matr. RM 021 ;

- digital caliber Mitutoyo matr. RM 073

For performing the test of resistance to break were obtained from the specimen of artificial leather fabric two series of five fabric specimens, one in longitudinal direction and the other in transversal direction, having dimensions 300 ± 1 mm x 50 ± 0,5mm.

Each specimen, after an initial conditioning of 24h a 23 ± 2°C and 50 ± 5% of relative umidity, was fixed at the clamps of the dynamometric machine adjusted at a distance of 200mm, and subjected to tension with a constant velocity equal to 100mm/min till break.

During the test the values were recorded of applied tension and elongation of the specimen reported in figures 8 and 9 concerning respectively the test of resistance to longitudinal and transversal break. The same data are resumed in the following table 7:

Table 7

Resistance to break

Specimen type specimen n. Maximum load at break (kN) 1 852,7

2 822,9

3 823,5

Longitudinal

4 856,6

5 874,6 average 847,5

1 934,2

2 873,8

3 876,6

Trasversal

4 921 ,8

5 860,4 average 893,3

For performing the test of percentage elongation under load from the sample of artificial leather fabric were obtained two series of seven specimens of fabric, one in longitudinal direction and the other in transversal direction, having dimensions 350 x 50mm.

On each specimen, conditioned for 24h at 23 ± 2°C and 50 ± 5% of relative umidity, two reference lines were drawn, positioned at 200mm from one another; the specimens were fixed to the clamps of the dynamometric machine at the distance of the reference signs.

The test was performed subjecting the specimens to tension till reaching an applied load equal to 100N; under these conditions the gauge length was measured and the elongation percentage was calculated. The measured results are reported in the following table 8:

Table 8

Elongation under load (100 N)

Specimen type specimen n. Elongation (%)

1 7,3

2 7,2

Longitudinal

3 7,4

4 7,1 5 7,0

6 6,9

7 7,0

average 7,1

1 6,0

2 5,9

3 5,6

4 5,7

Transversal

5 5,4

6 5,5

7 5,6

average 5,7

wherein the percentage elongation was calculated according to the following formula:

A% = 100 (LT - V

wherein L1 indicates the final length and L ₀ is the initial length (200mm).

In order to perform the test of resistance to tear from the sample of artificial leather fabric two series of five fabric specimens were obtained, one in longitudinal direction and the other in transversal direction, having dimensions 200mm x 150mm.

Each specimen, from which a tongue was cut measuring 100x50mm, was fixed at the clamps of the dynamometric machine adjusted at a distance of 100mm, so that half tongue is fixed in a clamp and the legs of the specimen are clamped in the other.

Under such conditions the tension was applied, with a velocity of 100 mm/min until the specimen is ripped for 60mm.

During the test the values were recorded of applied tension and elongation of the specimen reported in figures 10 and 11 concerning respectively the longitudinal and transversal tear tests. The same data are resumed in the following table 9:

Table 9 Specimen type specimen n. Average resistance to single specimens (kN)

1 0,129

2 0,114

3 0,123

Longitudinal

4 0,127

5 0,128

Average 0,124

1 0,061

2 0,073

3 0,059

Transversal

4 0,069

5 0,070

Average 0,066

In order to perform the tests of residual deformation under constant elongation from the sample of artificial leather fabric two series of five fabric specimens were obtained, one in longitudinal direction and the other in transversal direction, having dimensions 350 x 50mm.

On each specimen, conditioned for 24h at 23 ± 2°C and 50 ± 5% of relative umidity, two reference lines were drawn, positioned at 200mm from one another; the specimens were fixed to the clamps of the dynamometric machine at the distance of the reference signs.

Under such conditions tension was applied until an elongation was obtained of 50mm of the gauge length, maintained for 5h; after such period the specimens were freed from the machine and conditioned for 2h at 23 ± 2°C and 50 ± 2% of relative umidity. Finally it was measured the gauge length of the specimens and calculated the elongation percentage. The measured results are reported in the following table 10:

Table 10

Residual deformation after constant elongation (50mm)

Specimen type specimen n. Residual deformation (%)

1 29,1

2 28,7

3 27,8

Longitudinal

4 28,4

5 27,3

Average 28,3

1 30,6

2 30,1

3 28,5

Transversal

4 29,1

5 29,4

Average 29,6 wherein the percentage of residual deformation was calculated according to the following formula:

D _R % = 100 (LT - Lo)/(Lu - Lo)

wherein L1 indicates the final length, L ₀ is the initial length (200mm) and Lu is the length under tension.

The present invention was described for illustrative, non limitative purposes, according to its preferred embodiments, but it has to be understood that any variations and/or modifications can be made by the skilled in the art without departing from the relative scope of protection as defined by the enclosed claims.